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putnam_1978_a4
theorem putnam_1978_a4 (bypass : (S : Type) β†’ [inst : Mul S] β†’ Prop) (hbypass : bypass = fun S [Mul S] ↦ βˆ€ a b c d : S, (a * b) * (c * d) = a * d) : ((βˆ€ (S : Type) (_ : Mul S), bypass S β†’ βˆ€ a b c : S, a * b = c β†’ (c * c = c ∧ βˆ€ d : S, a * d = c * d)) ∧ (βˆƒ (S : Type) (_ : Mul S) (_ : Fintype S), bypass S ∧ (βˆ€ a : S, a * a = a) ∧ (βˆƒ a b : S, a * b = a ∧ a β‰  b) ∧ (βˆƒ a b : S, a * b β‰  a))) := sorry
334c81bdac4a7a55
putnam_2022_a6
abbrev putnam_2022_a6_solution : β„• β†’ β„• := sorry -- (fun n : β„• => n) /-- Let $n$ be a positive integer. Determine, in terms of $n$, the largest integer $m$ with the following property: There exist real numbers $x_1,\dots,x_{2n}$ with $-1<x_1<x_2<\cdots<x_{2n}<1$ such that the sum of the lengths of the $n$ intervals $[x_1^{2k-1},x_2^{2k-1}],[x_3^{2k-1},x_4^{2k-1}],\dots,[x_{2n-1}^{2k-1},x_{2n}^{2k-1}]$ is equal to $1$ for all integers $k$ with $1 \leq k \leq m$. -/ theorem putnam_2022_a6 (n : β„•) (hn : 0 < n) : IsGreatest {m : β„• | βˆƒ x : β„• β†’ ℝ, StrictMono x ∧ -1 < x 1 ∧ x (2 * n) < 1 ∧ βˆ€ k ∈ Icc 1 m, βˆ‘ i in Icc 1 n, ((x (2 * i) : ℝ) ^ (2 * k - 1) - (x (2 * i - 1)) ^ (2 * k - 1)) = 1} (putnam_2022_a6_solution n) := sorry
23a94c220ea3b0a5
putnam_2010_b2
abbrev putnam_2010_b2_solution : β„• := sorry -- 3 /-- Given that $A$, $B$, and $C$ are noncollinear points in the plane with integer coordinates such that the distances $AB$, $AC$, and $BC$ are integers, what is the smallest possible value of $AB$? -/ theorem putnam_2010_b2 (ABCintcoords ABCintdists ABCall: EuclideanSpace ℝ (Fin 2) β†’ EuclideanSpace ℝ (Fin 2) β†’ EuclideanSpace ℝ (Fin 2) β†’ Prop) (hABCintcoords : βˆ€ A B C, ABCintcoords A B C ↔ (βˆ€ i : Fin 2, A i = round (A i) ∧ B i = round (B i) ∧ C i = round (C i))) (hABCintdists : βˆ€ A B C, ABCintdists A B C ↔ (dist A B = round (dist A B) ∧ dist A C = round (dist A C) ∧ dist B C = round (dist B C))) (hABCall : βˆ€ A B C, ABCall A B C ↔ (Β¬Collinear ℝ {A, B, C} ∧ ABCintcoords A B C ∧ ABCintdists A B C)) : IsLeast {y | βˆƒ A B C, ABCall A B C ∧ y = dist A B} putnam_2010_b2_solution := sorry
557b3e7ddcd06891
putnam_2000_b2
theorem putnam_2000_b2 : (βˆ€ m n : β„•, m β‰₯ 1 β†’ n β‰₯ m β†’ n ∣ Nat.gcd m n * Nat.choose n m) := sorry
ed011644bfce06ca
putnam_2019_a4
abbrev putnam_2019_a4_solution : Prop := sorry -- False /-- Let $f$ be a continuous real-valued function on $\mathbb{R}^3$. Suppose that for every sphere $S$ of radius $1$, the integral of $f(x,y,z)$ over the surface of $S$ equals $0$. Must $f(x,y,z)$ be identically 0? -/ theorem putnam_2019_a4 (P : (EuclideanSpace ℝ (Fin 3) β†’ ℝ) β†’ Prop) (P_def : βˆ€ f, P f ↔ βˆ€ C, ∫ x in sphere C 1, f x βˆ‚ΞΌH[2] = 0) : (βˆ€ f, Continuous f β†’ P f β†’ f = 0) ↔ putnam_2019_a4_solution := sorry
47c50ab4e42f3f14
putnam_2009_a4
abbrev putnam_2009_a4_solution : Prop := sorry -- False /-- Let $S$ be a set of rational numbers such that \begin{enumerate} \item[(a)] $0 \in S$; \item[(b)] If $x \in S$ then $x+1\in S$ and $x-1\in S$; and \item[(c)] If $x\in S$ and $x\not\in\{0,1\}$, then $\frac{1}{x(x-1)}\in S$. \end{enumerate} Must $S$ contain all rational numbers? -/ theorem putnam_2009_a4 : ((βˆ€ S : Set β„š, 0 ∈ S β†’ (βˆ€ x ∈ S, x + 1 ∈ S ∧ x - 1 ∈ S) β†’ (βˆ€ x ∈ S, x βˆ‰ ({0, 1} : Set β„š) β†’ 1 / (x * (x - 1)) ∈ S) β†’ βˆ€ r : β„š, r ∈ S) ↔ putnam_2009_a4_solution) := sorry
5d5e527fd9614911
putnam_2024_a3
abbrev putnam_2024_a3_solution : Prop := sorry --True /-- Let $S$ be the set of bijections $$T : \{1, 2, 3\} \times \{1, 2, ..., 2024\} \to \{1, 2, ..., 6072\}$$ such that $T(1, j) < T(2, j) < T(3, j)$ for all $j \in \{1, 2, ..., 2024\}$ and $T(i, j) < T(i, j + 1)$ for all $i \in \{1, 2, 3\}$ and $j \in \{1, 2, ..., 2023\}$. Do there exist $a, c$ in $\{1, 2, 3\}$ and $b$ and $d$ in $\{1, 2, ..., 2024\}$ such that the fraction of elements $T$ in $S$ for which $T(a, b) < T(c, d)$ is at least $1/3$ and at most $2/3$? -/ theorem putnam_2024_a3 (S : Set (β„• Γ— β„• β†’ β„•)) (hS : S = {T | Set.BijOn T (Finset.Icc 1 3 Γ—Λ’ Finset.Icc 1 2024) (Finset.Icc 1 6072) ∧ (βˆ€ j ∈ Finset.Icc 1 2024, StrictMonoOn (fun i => T (i, j)) (Set.Icc 1 3)) ∧ (βˆ€ i ∈ Finset.Icc 1 3, StrictMonoOn (fun j => T (i, j)) (Set.Icc 1 2024)) ∧ (βˆ€ x, x βˆ‰ Finset.Icc 1 3 Γ—Λ’ Finset.Icc 1 2024 β†’ T x = 0)}) : (βˆƒ a ∈ Finset.Icc 1 3, βˆƒ b ∈ Finset.Icc 1 2024, βˆƒ c ∈ Finset.Icc 1 3, βˆƒ d ∈ Finset.Icc 1 2024, ({T | T ∈ S ∧ T (a, b) < T (c, d)}.ncard / S.ncard : β„š) ∈ Set.Icc (1/3) (2/3)) ↔ putnam_2024_a3_solution := sorry
ba30a2d351b304b4
putnam_1971_b2
abbrev putnam_1971_b2_solution : Set (ℝ β†’ ℝ) := sorry -- {fun x : ℝ => (x^3 - x^2 - 1)/(2 * x * (x - 1))} /-- Find all functions $F : \mathbb{R} \setminus \{0, 1\} \to \mathbb{R}$ that satisfy $F(x) + F\left(\frac{x - 1}{x}\right) = 1 + x$ for all $x \in \mathbb{R} \setminus \{0, 1\}$. -/ theorem putnam_1971_b2 (S : Set ℝ) (hS : S = univ \ {0, 1}) (P : (ℝ β†’ ℝ) β†’ Prop) (hP : P = fun (F : ℝ β†’ ℝ) => βˆ€ x ∈ S, F x + F ((x - 1)/x) = 1 + x) : (βˆ€ F ∈ putnam_1971_b2_solution, P F) ∧ βˆ€ f : ℝ β†’ ℝ, P f β†’ βˆƒ F ∈ putnam_1971_b2_solution, (βˆ€ x ∈ S, f x = F x) := sorry
9bcd4567c23d131c
putnam_2001_b3
abbrev putnam_2001_b3_solution : ℝ := sorry -- 3 /-- For any positive integer $n$, let $\langle n \rangle$ denote the closest integer to $\sqrt{n}$. Evaluate $\sum_{n=1}^\infty \frac{2^{\langle n \rangle}+2^{-\langle n \rangle}}{2^n}$. -/ theorem putnam_2001_b3 : βˆ‘' n : Set.Ici 1, ((2 : ℝ) ^ (round (Real.sqrt n)) + (2 : ℝ) ^ (-round (Real.sqrt n))) / 2 ^ (n : ℝ) = putnam_2001_b3_solution := sorry
ee626e2c3fb370a2
putnam_2011_b3
abbrev putnam_2011_b3_solution : Prop := sorry -- True /-- Let $f$ and $g$ be (real-valued) functions defined on an open interval containing $0$, with $g$ nonzero and continuous at $0$. If $fg$ and $f/g$ are differentiable at $0$, must $f$ be differentiable at $0$? -/ theorem putnam_2011_b3 : ((βˆ€ f g : ℝ β†’ ℝ, g 0 β‰  0 β†’ ContinuousAt g 0 β†’ DifferentiableAt ℝ (fun x ↦ f x * g x) 0 β†’ DifferentiableAt ℝ (fun x ↦ f x / g x) 0 β†’ (DifferentiableAt ℝ f 0)) ↔ putnam_2011_b3_solution) := sorry
aaa710ef0e9af4cf
putnam_1966_b6
theorem putnam_1966_b6 (y : ℝ β†’ ℝ) (hy : Differentiable ℝ y ∧ Differentiable ℝ (deriv y)) (diffeq : deriv (deriv y) + Real.exp * y = 0) : βˆƒ r s N : ℝ, βˆ€ x > N, r ≀ y x ∧ y x ≀ s := sorry
374a451254b51fec
putnam_1976_b6
theorem putnam_1976_b6 (Οƒ : β„• β†’ β„€) (hΟƒ : Οƒ = fun N : β„• => βˆ‘ d in Nat.divisors N, (d : β„€)) (quasiperfect : β„• β†’ Prop) (quasiperfect_def : βˆ€ N, quasiperfect N ↔ Οƒ N = 2*N + 1) : βˆ€ N : β„•, quasiperfect N β†’ βˆƒ m : β„€, Odd m ∧ m^2 = N := sorry
996ef5b82e155a2a
putnam_1979_a5
theorem putnam_1979_a5 (S : ℝ β†’ β„• β†’ β„€) (hS : S = fun x : ℝ => fun n : β„• => Int.floor (n*x)) (P : ℝ β†’ Prop) (hP : βˆ€ x, P x ↔ x^3 - 10*x^2 + 29*x - 25 = 0) : βˆƒ Ξ± Ξ² : ℝ, Ξ± β‰  Ξ² ∧ P Ξ± ∧ P Ξ² ∧ βˆ€ n : β„•, βˆƒ m : β„€, m > n ∧ βˆƒ c d : β„•, S Ξ± c = m ∧ S Ξ² d = m := sorry
e119f47714efe05f
putnam_1994_b3
abbrev putnam_1994_b3_solution : Set ℝ := sorry -- Set.Iio 1 /-- Find the set of all real numbers $k$ with the following property: For any positive, differentiable function $f$ that satisfies $f'(x)>f(x)$ for all $x$, there is some number $N$ such that $f(x)>e^{kx}$ for all $x>N$. -/ theorem putnam_1994_b3 : {k | βˆ€ f (hf : (βˆ€ x, 0 < f x ∧ f x < deriv f x) ∧ Differentiable ℝ f), βˆƒ N, βˆ€ x > N, Real.exp (k * x) < f x} = putnam_1994_b3_solution := sorry
96841a25380621c6
putnam_1969_a5
theorem putnam_1969_a5 (x0 y0 t : ℝ) (ht : 0 < t) : x0 = y0 ↔ βˆƒ x y u : ℝ β†’ ℝ, Differentiable ℝ x ∧ Differentiable ℝ y ∧ Continuous u ∧ deriv x = - 2 β€’ y + u ∧ deriv y = - 2 β€’ x + u ∧ x 0 = x0 ∧ y 0 = y0 ∧ x t = 0 ∧ y t = 0 := sorry
25332e9b27d1d921
putnam_1984_b3
abbrev putnam_1984_b3_solution : Prop := sorry -- True /-- Prove or disprove the following statement: If $F$ is a finite set with two or more elements, then there exists a binary operation $*$ on F such that for all $x,y,z$ in $F$, \begin{enumerate} \item[(i)] $x*z=y*z$ implies $x=y$ (right cancellation holds), and \item[(ii)] $x*(y*z) \neq (x*y)*z$ (\emph{no} case of associativity holds). \end{enumerate} -/ theorem putnam_1984_b3 : (βˆ€ (F : Type*) (_ : Fintype F), Fintype.card F β‰₯ 2 β†’ (βˆƒ mul : F β†’ F β†’ F, βˆ€ x y z : F, (mul x z = mul y z β†’ x = y) ∧ (mul x (mul y z) β‰  mul (mul x y) z))) ↔ putnam_1984_b3_solution := sorry
a493ab2d09dfdae3
putnam_1987_b5
theorem putnam_1987_b5 (n : β„•) (npos : n > 0) (M : Matrix (Fin (2 * n)) (Fin n) β„‚) (hM : βˆ€ z : Matrix (Fin 1) (Fin (2 * n)) β„‚, z * M = 0 β†’ (Β¬βˆ€ i : Fin (2 * n), z 0 i = 0) β†’ βˆƒ i : Fin (2 * n), (z 0 i).im β‰  0) : (βˆ€ r : Matrix (Fin (2 * n)) (Fin 1) ℝ, βˆƒ w : Matrix (Fin n) (Fin 1) β„‚, βˆ€ i : (Fin (2 * n)), ((M * w) i 0).re = r i 0) := sorry
1e761ad9a668c583
putnam_1997_b5
theorem putnam_1997_b5 (n : β„•) (hn : n β‰₯ 2) : tetration 2 n ≑ tetration 2 (n-1) [MOD n] := sorry
32ebbc8716c03f4c
putnam_2012_b5
theorem putnam_2012_b5 (g1 g2 : ℝ β†’ ℝ) (hgim : βˆ€ x : ℝ, g1 x β‰₯ 1 ∧ g2 x β‰₯ 1) (hgbd : βˆƒ B1 B2 : ℝ, βˆ€ x : ℝ, g1 x ≀ B1 ∧ g2 x ≀ B2) : βˆƒ h1 h2 : ℝ β†’ ℝ, βˆ€ x : ℝ, sSup {((g1 s)^x * (g2 s)) | s : ℝ} = sSup {(x * (h1 t) + h2 t) | t : ℝ} := sorry
3e1b7c0315d3d306
putnam_2002_b5
theorem putnam_2002_b5 : βˆƒ n : β„•, {b : β„• | b β‰₯ 1 ∧ (Nat.digits b n).length = 3 ∧ List.Palindrome (Nat.digits b n)}.ncard β‰₯ 2002 := sorry
b1ea4f2c84839df6
putnam_1998_a6
theorem putnam_1998_a6 (A B C : EuclideanSpace ℝ (Fin 2)) (hint : βˆ€ i : Fin 2, βˆƒ a b c : β„€, A i = a ∧ B i = b ∧ C i = c) (htriangle : A β‰  B ∧ A β‰  C ∧ B β‰  C) (harea : (dist A B + dist B C) ^ 2 < 8 * (MeasureTheory.volume (convexHull ℝ {A, B, C})).toReal + 1) (threesquare : (EuclideanSpace ℝ (Fin 2)) β†’ (EuclideanSpace ℝ (Fin 2)) β†’ (EuclideanSpace ℝ (Fin 2)) β†’ Prop) (threesquare_def : threesquare = fun P Q R ↦ dist Q P = dist Q R ∧ βŸͺP - Q, R - Q⟫_ℝ = 0) : (threesquare A B C ∨ threesquare B C A ∨ threesquare C A B) := sorry
901f127e8be3074f
putnam_2020_a1
abbrev putnam_2020_a1_solution : β„• := sorry -- 508536 /-- Find the number of positive integers $N$ satisfying: (i) $N$ is divisible by $2020$, (ii) $N$ has at most $2020$ decimal digits, (iii) The decimal digits of $N$ are a string of consecutive ones followed by a string of consecutive zeros. -/ theorem putnam_2020_a1 : Set.ncard {x : β„• | (2020 ∣ x) ∧ (Nat.log 10 x) + 1 ≀ 2020 ∧ (βˆƒ k l, k β‰₯ l ∧ x = βˆ‘ i in Finset.range (k-l+1), 10 ^ (i+l))} = putnam_2020_a1_solution := sorry
8b30c97573ce448f
putnam_1988_a6
abbrev putnam_1988_a6_solution : Prop := sorry -- True /-- If a linear transformation $A$ on an $n$-dimensional vector space has $n+1$ eigenvectors such that any $n$ of them are linearly independent, does it follow that $A$ is a scalar multiple of the identity? Prove your answer. -/ theorem putnam_1988_a6 : (βˆ€ (F V : Type*) (_ : Field F) (_ : AddCommGroup V) (_ : Module F V) (_ : FiniteDimensional F V) (n : β„•) (A : Module.End F V) (evecs : Set V), (n = Module.finrank F V ∧ evecs βŠ† {v : V | βˆƒ f : F, A.HasEigenvector f v} ∧ evecs.encard = n + 1 ∧ (βˆ€ sevecs : Fin n β†’ V, (Set.range sevecs βŠ† evecs ∧ (Set.range sevecs).encard = n) β†’ LinearIndependent F sevecs)) β†’ (βˆƒ c : F, A = c β€’ LinearMap.id)) ↔ putnam_1988_a6_solution := sorry
fcbcffc8e57f2d07
putnam_2015_b1
theorem putnam_2015_b1 (f : ℝ β†’ ℝ) (nzeros : (ℝ β†’ ℝ) β†’ β„• β†’ Prop) (fdiff : ContDiff ℝ 2 f ∧ Differentiable ℝ (iteratedDeriv 2 f)) (hnzeros : βˆ€ f' : ℝ β†’ ℝ, βˆ€ n : β„•, nzeros f' n = ({x : ℝ | f' x = 0}.encard β‰₯ n)) (fzeros : nzeros f 5) : nzeros (f + 6 * deriv f + 12 * iteratedDeriv 2 f + 8 * iteratedDeriv 3 f) 2 := sorry
9af92b96aa448cca
putnam_2005_b1
abbrev putnam_2005_b1_solution : MvPolynomial (Fin 2) ℝ := sorry -- (MvPolynomial.X 1 - 2 * MvPolynomial.X 0) * (MvPolynomial.X 1 - 2 * MvPolynomial.X 0 - 1) /-- Find a nonzero polynomial $P(x,y)$ such that $P(\lfloor a \rfloor,\lfloor 2a \rfloor)=0$ for all real numbers $a$. (Note: $\lfloor \nu \rfloor$ is the greatest integer less than or equal to $\nu$.) -/ theorem putnam_2005_b1 : putnam_2005_b1_solution β‰  0 ∧ βˆ€ a : ℝ, MvPolynomial.eval (fun n : Fin 2 => if (n = 0) then (Int.floor a : ℝ) else (Int.floor (2 * a))) putnam_2005_b1_solution = 0 := sorry
5b82fc7c3e7bc40b
putnam_1972_b4
theorem putnam_1972_b4 (n : β„•) (hn : n > 1) (vars : β„€ β†’ β„€ β†’ β„€ β†’ (Fin 3 β†’ β„€)) (hvars : vars = fun a b c ↦ fun i ↦ ite (i = 0) a (ite (i = 1) b c)) : βˆƒ P : MvPolynomial (Fin 3) β„€, βˆ€ x : β„€, x = MvPolynomial.eval (vars (x^n) (x^(n+1)) (x + x^(n+2))) P := sorry
fb9052ce93417245
putnam_1980_b1
abbrev putnam_1980_b1_solution : Set ℝ := sorry -- {c : ℝ | c β‰₯ 1 / 2} /-- For which real numbers $c$ is $(e^x+e^{-x})/2 \leq e^{cx^2}$ for all real $x$? -/ theorem putnam_1980_b1 (c : ℝ) : (βˆ€ x : ℝ, (exp x + exp (-x)) / 2 ≀ exp (c * x ^ 2)) ↔ c ∈ putnam_1980_b1_solution := sorry
d74af7f38f92cd8f
putnam_1990_b1
abbrev putnam_1990_b1_solution : Set (ℝ β†’ ℝ) := sorry -- {fun x : ℝ => (Real.sqrt 1990) * Real.exp x, fun x : ℝ => -(Real.sqrt 1990) * Real.exp x} /-- Find all real-valued continuously differentiable functions $f$ on the real line such that for all $x$, $(f(x))^2=\int_0^x [(f(t))^2+(f'(t))^2]\,dt+1990$. -/ theorem putnam_1990_b1 (P : (ℝ β†’ ℝ) β†’ Prop) (P_def : βˆ€ f, P f ↔ βˆ€ x, (f x) ^ 2 = (∫ t in (0 : ℝ)..x, (f t) ^ 2 + (deriv f t) ^ 2) + 1990) (f : ℝ β†’ ℝ) : (ContDiff ℝ 1 f ∧ P f) ↔ f ∈ putnam_1990_b1_solution := sorry
2661f3261c98e78b
putnam_1984_a5
abbrev putnam_1984_a5_solution : β„• Γ— β„• Γ— β„• Γ— β„• Γ— β„• := sorry -- (1, 9, 8, 4, 25) /-- Let $R$ be the region consisting of all triples $(x,y,z)$ of nonnegative real numbers satisfying $x+y+z \leq 1$. Let $w=1-x-y-z$. Express the value of the triple integral $\iiint_R x^1y^9z^8w^4\,dx\,dy\,dz$ in the form $a!b!c!d!/n!$, where $a$, $b$, $c$, $d$, and $n$ are positive integers. -/ theorem putnam_1984_a5 (R : Set (Fin 3 β†’ ℝ)) (w : (Fin 3 β†’ ℝ) β†’ ℝ) (hR : R = {p | (βˆ€ i : Fin 3, p i β‰₯ 0) ∧ p 0 + p 1 + p 2 ≀ 1}) (hw : βˆ€ p, w p = 1 - p 0 - p 1 - p 2) : let (a, b, c, d, n) := putnam_1984_a5_solution; a > 0 ∧ b > 0 ∧ c > 0 ∧ d > 0 ∧ n > 0 ∧ (∫ p in R, (p 0) ^ 1 * (p 1) ^ 9 * (p 2) ^ 8 * (w p) ^ 4 = ((a)! * (b)! * (c)! * (d)! : ℝ) / (n)!) := sorry
fe6312600dff5dd7
putnam_1969_b3
theorem putnam_1969_b3 (T : β„• β†’ ℝ) (hT1 : βˆ€ n : β„•, n β‰₯ 1 β†’ (T n) * (T (n + 1)) = n) (hT2 : Tendsto (fun n => (T n)/(T (n + 1))) atTop (𝓝 1)) : Real.pi * (T 1)^2 = 2 := sorry
16372ab48fd3908e
putnam_1994_a5
theorem putnam_1994_a5 (r : β„• β†’ ℝ) (S : Set ℝ) (rpos : βˆ€ n, r n > 0) (rlim : Tendsto r atTop (𝓝 0)) (hS : S = {x | βˆƒ i : Fin 1994 β†’ β„•, (βˆ€ j k : Fin 1994, j < k β†’ i j < i k) ∧ (x = βˆ‘ j : Fin 1994, r (i j))}) : βˆ€ a b : ℝ, a < b β†’ (βˆƒ c d : ℝ, a ≀ c ∧ c < d ∧ d ≀ b ∧ (Set.Ioo c d) ∩ S = βˆ…) := sorry
5dbd1f9747ed51a5
putnam_1979_b3
abbrev putnam_1979_b3_solution : β„• β†’ β„€ := sorry -- fun n ↦ (n - 1) / 2 /-- Let $F$ be a finite field with $n$ elements, and assume $n$ is odd. Suppose $x^2 + bx + c$ is an irreducible polynomial over $F$. For how many elements $d \in F$ is $x^2 + bx + c + d$ irreducible? -/ theorem putnam_1979_b3 (F : Type*) [Field F] [Fintype F] (n : β„•) (hn : n = Fintype.card F) (nodd : Odd n) (b c : F) (p : Polynomial F) (hp : p = X ^ 2 + (C b) * X + (C c) ∧ Irreducible p) : ({d : F | Irreducible (p + (C d))}.ncard = putnam_1979_b3_solution n) := sorry
a7d55170758e337c
putnam_2023_b1
abbrev putnam_2023_b1_solution : β„• β†’ β„• β†’ β„• := sorry -- (fun m n : β„• => Nat.choose (m + n - 2) (m - 1)) /-- Consider an $m$-by-$n$ grid of unit squares, indexed by $(i,j)$ with $1 \leq i \leq m$ and $1 \leq j \leq n$. There are $(m-1)(n-1)$ coins, which are initially placed in the squares $(i,j)$ with $1 \leq i \leq m-1$ and $1 \leq j \leq n-1$. If a coin occupies the square $(i,j)$ with $i \leq m-1$ and $j \leq n-1$ and the squares $(i+1,j)$, $(i,j+1)$, and $(i+1,j+1)$ are unoccupied, then a legal move is to slide the coin from $(i,j)$ to $(i+1,j+1)$. How many distinct configurations of coins can be reached starting from the initial configuration by a (possibly empty) sequence of legal moves? -/ theorem putnam_2023_b1 (m n : β„•) (initcoins : β„• β†’ β„• β†’ Bool) (hinitcoins : initcoins = (fun i j : β„• => (i ≀ m - 2 ∧ j ≀ n - 2 : Bool))) (IsLegalMove : (β„• β†’ β„• β†’ Bool) β†’ (β„• β†’ β„• β†’ Bool) β†’ Prop) (IsLegalMove_def : βˆ€ coins1 coins2, IsLegalMove coins1 coins2 ↔ βˆƒ i j, i < m - 1 ∧ j < n - 1 ∧ coins1 i j ∧ !coins1 (i + 1) j ∧ !coins1 i (j + 1) ∧ !coins1 (i + 1) (j + 1) ∧ !coins2 i j ∧ !coins2 (i + 1) j ∧ !coins2 i (j + 1) ∧ coins2 (i + 1) (j + 1) ∧ (βˆ€ i' j', ((i', j') β‰  (i, j) ∧ (i', j') β‰  (i + 1, j) ∧ (i', j') β‰  (i, j + 1) ∧ (i', j') β‰  (i + 1, j + 1)) β†’ coins1 i' j' = coins2 i' j')) (IsLegalSeq : List (β„• β†’ β„• β†’ Bool) β†’ Prop) (IsLegalSeq_def : βˆ€ seq, IsLegalSeq seq ↔ seq.length β‰₯ 1 ∧ seq[0]! = initcoins ∧ (βˆ€ i < seq.length - 1, IsLegalMove seq[i]! seq[i + 1]!)) (mnpos : 1 < m ∧ 1 < n) : {config : β„• β†’ β„• β†’ Bool | βˆƒ seq : List (β„• β†’ β„• β†’ Bool), IsLegalSeq seq ∧ config = seq.getLast!}.encard = putnam_2023_b1_solution m n := sorry
7cf9991a66d49206
putnam_2011_a5
theorem putnam_2011_a5 (F : (Fin 2 β†’ ℝ) β†’ ℝ) (g : ℝ β†’ ℝ) (vec : ℝ β†’ ℝ β†’ (Fin 2 β†’ ℝ)) (Fgrad : (Fin 2 β†’ ℝ) β†’ (Fin 2 β†’ ℝ)) (parallel : (Fin 2 β†’ ℝ) β†’ (Fin 2 β†’ ℝ) β†’ Prop) (hparallel : parallel = (fun u v : Fin 2 β†’ ℝ => βˆƒ c : ℝ, u = c β€’ v)) (Fgdiff : ContDiff ℝ 2 F ∧ ContDiff ℝ 2 g) (prop1 : βˆ€ uu : Fin 2 β†’ ℝ, uu 0 = uu 1 β†’ F uu = 0) (prop2 : βˆ€ x : ℝ, g x > 0 ∧ x ^ 2 * g x ≀ 1) (hvec : βˆ€ x y : ℝ, (vec x y) 0 = x ∧ (vec x y) 1 = y) (hFgrad : βˆ€ uv : Fin 2 β†’ ℝ, Fgrad uv 0 = deriv (fun x : ℝ => F (vec x (uv 1))) (uv 0) ∧ Fgrad uv 1 = deriv (fun y : ℝ => F (vec (uv 0) y)) (uv 1)) (prop3 : βˆ€ uv : Fin 2 β†’ ℝ, Fgrad uv = 0 ∨ parallel (Fgrad uv) (vec (g (uv 0)) (-g (uv 1)))) : βˆƒ C : ℝ, βˆ€ n β‰₯ 2, βˆ€ x : Fin (n + 1) β†’ ℝ, sInf {Fxx : ℝ | βˆƒ i j : Fin (n + 1), i β‰  j ∧ Fxx = |F (vec (x i) (x j))|} ≀ C / n := sorry
a0914c24d8c29742
putnam_2001_a5
theorem putnam_2001_a5 : βˆƒ! an : β„€ Γ— β„•, let (a, n) := an; a > 0 ∧ n > 0 ∧ a^(n+1) - (a+1)^n = 2001 := sorry
2dd9ca5be69002fc
putnam_1971_a4
theorem putnam_1971_a4 (Ξ΅ : ℝ) (hΞ΅ : 0 < Ξ΅ ∧ Ξ΅ < 1) (P : β„• β†’ ℝ β†’ MvPolynomial (Fin 2) ℝ) (hP : P = fun (n : β„•) (Ξ΄ : ℝ) => (MvPolynomial.X 0 + MvPolynomial.X 1)^n * ((MvPolynomial.X 0)^2 - (MvPolynomial.C (2 - Ξ΄))*(MvPolynomial.X 0)*(MvPolynomial.X 1) + (MvPolynomial.X 1)^2)) : βˆƒ N : β„•, βˆ€ n β‰₯ N, βˆ€ i : Fin 2 β†’β‚€ β„•, MvPolynomial.coeff i (P n Ξ΅) β‰₯ 0 := sorry
52cdd9017602529a
putnam_2024_b5
theorem putnam_2024_b5 (IsQualifyingSeq : {q : β„•} β†’ (Fin q β†’ β„•) β†’ β„• β†’ Prop) (IsQualifyingSeq_def : βˆ€ q w z, βˆ€ [NeZero q], IsQualifyingSeq w z ↔ Monotone w ∧ 1 ≀ w 0 ∧ w (-1 : Fin q) ≀ z) (k m : β„•) [NeZero k] [NeZero m] (f : β„• β†’ β„•) (f_def : βˆ€ n, f n = {(x, y, z) : (Fin k β†’ β„•) Γ— (Fin m β†’ β„•) Γ— β„• | IsQualifyingSeq x z ∧ IsQualifyingSeq y z ∧ z ≀ n}.ncard) : βˆƒ P : β„š[X], (βˆ€ n > 0, f n = P.eval (n : β„š)) ∧ (βˆ€ i, 0 ≀ P.coeff i) := sorry
534c4adee8639ec0
putnam_2016_a1
abbrev putnam_2016_a1_solution : β„• := sorry -- 8 /-- Find the smallest positive integer $j$ such that for every polynomial $p(x)$ with integer coefficients and for every integer $k$, the integer \[ p^{(j)}(k) = \left. \frac{d^j}{dx^j} p(x) \right|_{x=k} \] (the $j$-th derivative of $p(x)$ at $k$) is divisible by 2016. -/ theorem putnam_2016_a1 : IsLeast {j : β„• | 0 < j ∧ βˆ€ P : β„€[X], βˆ€ k : β„€, 2016 ∣ (derivative^[j] P).eval k} putnam_2016_a1_solution := sorry
03c43aebbf02eb17
putnam_2006_a1
abbrev putnam_2006_a1_solution : ℝ := sorry -- 6 * Real.pi ^ 2 /-- Find the volume of the region of points $(x,y,z)$ such that \[ (x^2 + y^2 + z^2 + 8)^2 \leq 36(x^2 + y^2). \] -/ theorem putnam_2006_a1 : ((MeasureTheory.volume {(x, y, z) : ℝ Γ— ℝ Γ— ℝ | (x ^ 2 + y ^ 2 + z ^ 2 + 8) ^ 2 ≀ 36 * (x ^ 2 + y ^ 2)}).toReal = putnam_2006_a1_solution) := sorry
36e42ea769659c68
putnam_1983_a1
abbrev putnam_1983_a1_solution : β„• := sorry -- 2301 /-- How many positive integers $n$ are there such that $n$ is an exact divisor of at least one of the numbers $10^{40},20^{30}$? -/ theorem putnam_1983_a1 : {n : β„€ | n > 0 ∧ (n ∣ 10 ^ 40 ∨ n ∣ 20 ^ 30)}.encard = putnam_1983_a1_solution := sorry
494eae0724242169
putnam_1993_a1
abbrev putnam_1993_a1_solution : ℝ := sorry -- 4 / 9 /-- The horizontal line $y=c$ intersects the curve $y=2x-3x^3$ in the first quadrant as in the figure. Find $c$ so that the areas of the two shaded regions are equal. [Figure not included. The first region is bounded by the $y$-axis, the line $y=c$ and the curve; the other lies under the curve and above the line $y=c$ between their two points of intersection.] -/ theorem putnam_1993_a1 : 0 < putnam_1993_a1_solution ∧ putnam_1993_a1_solution < (4 * Real.sqrt 2) / 9 ∧ (∫ x in Set.Ioo 0 ((Real.sqrt 2) / 3), max (putnam_1993_a1_solution - (2 * x - 3 * x ^ 3)) 0) = (∫ x in Set.Ioo 0 ((Real.sqrt 6) / 3), max ((2 * x - 3 * x ^ 3) - putnam_1993_a1_solution) 0) := sorry
581e929d21e2c8ee
putnam_2009_b2
abbrev putnam_2009_b2_solution : Set ℝ := sorry -- Ioc (1 / 3) 1 /-- A game involves jumping to the right on the real number line. If $a$ and $b$ are real numbers and $b > a$, the cost of jumping from $a$ to $b$ is $b^3-ab^2$. For what real numbers $c$ can one travel from $0$ to $1$ in a finite number of jumps with total cost exactly $c$? -/ theorem putnam_2009_b2 : ({c : ℝ | βˆƒ s : β„• β†’ ℝ, s 0 = 0 ∧ StrictMono s ∧ (βˆƒ n : β„•, s n = 1 ∧ ((βˆ‘ i in Finset.range n, ((s (i + 1)) ^ 3 - (s i) * (s (i + 1)) ^ 2)) = c))} = putnam_2009_b2_solution) := sorry
fac39177bfae5cf0
putnam_2019_b2
abbrev putnam_2019_b2_solution : ℝ := sorry -- 8/Real.pi^3 /-- For all $n \geq 1$, let \[ a_n = \sum_{k=1}^{n-1} \frac{\sin \left( \frac{(2k-1)\pi}{2n} \right)}{\cos^2 \left( \frac{(k-1)\pi}{2n} \right) \cos^2 \left( \frac{k\pi}{2n} \right)}. \] Determine \[ \lim_{n \to \infty} \frac{a_n}{n^3}. \] -/ theorem putnam_2019_b2 (a : β„• β†’ ℝ) (ha : a = fun n : β„• => βˆ‘ k : Icc (1 : β„€) (n - 1), Real.sin ((2*k - 1)*Real.pi/(2*n))/((Real.cos ((k - 1)*Real.pi/(2*n))^2)*(Real.cos (k*Real.pi/(2*n))^2))) : Tendsto (fun n : β„• => (a n)/n^3) atTop (𝓝 putnam_2019_b2_solution) := sorry
e0048563f684a2c4
putnam_1962_a2
abbrev putnam_1962_a2_solution : Set (ℝ β†’ ℝ) := sorry -- {f : ℝ β†’ ℝ | βˆƒ a c : ℝ, a β‰₯ 0 ∧ f = fun x ↦ a / (1 - c * x) ^ 2} /-- Find every real-valued function $f$ whose domain is an interval $I$ (finite or infinite) having 0 as a left-hand endpoint, such that for every positive member $x$ of $I$ the average of $f$ over the closed interval $[0, x]$ is equal to the geometric mean of the numbers $f(0)$ and $f(x)$. -/ theorem putnam_1962_a2 (P : Set ℝ β†’ (ℝ β†’ ℝ) β†’ Prop) (P_def : βˆ€ s f, P s f ↔ 0 ≀ f ∧ βˆ€ x ∈ s, ⨍ t in Ico 0 x, f t = √(f 0 * f x)) : (βˆ€ f, (P (Ioi 0) f β†’ βˆƒ g ∈ putnam_1962_a2_solution, EqOn f g (Ici 0)) ∧ (βˆ€ e > 0, P (Ioo 0 e) f β†’ βˆƒ g ∈ putnam_1962_a2_solution, EqOn f g (Ico 0 e))) ∧ βˆ€ f ∈ putnam_1962_a2_solution, P (Ioi 0) f ∨ (βˆƒ e > 0, P (Ioo 0 e) f) := sorry
31a647955d81d399
putnam_1972_a2
theorem putnam_1972_a2 : (βˆ€ (S : Type*) (_ : Mul S), (βˆ€ x y : S, x * (x * y) = y ∧ ((y * x) * x) = y) β†’ (βˆ€ x y : S, x * y = y * x)) ∧ βˆƒ (S : Type*) (_ : Mul S), (βˆ€ x y : S, x * (x * y) = y ∧ ((y * x) * x) = y) ∧ Β¬(βˆ€ x y z : S, x * (y * z) = (x * y) * z) := sorry
031f9358a653e9dc
putnam_1965_a6
theorem putnam_1965_a6 (u v m : ℝ) (hu : 0 < u) (hv : 0 < v) (hm : 1 < m) : (βˆƒα΅‰ (x > 0) (y > 0), u * x + v * y = 1 ∧ x ^ m + y ^ m = 1 ∧ u = x ^ (m - 1) ∧ v = y ^ (m - 1)) ↔ βˆƒ n, u ^ n + v ^ n = 1 ∧ m⁻¹ + n⁻¹ = 1 := sorry
85e0f90cb4308080
putnam_2002_a3
theorem putnam_2002_a3 (n Tn : β„€) (hn : n β‰₯ 2) (hTn : Tn = Set.ncard {S : Set β„€ | S βŠ† Set.Icc 1 n ∧ Nonempty S ∧ βˆƒ k : β„€, k = ((1 : ℝ) / S.ncard) * (βˆ‘' s : S, s.1)}) : Even (Tn - n) := sorry
292e7385d3d83d07
putnam_2012_a3
abbrev putnam_2012_a3_solution : ℝ β†’ ℝ := sorry -- fun x : ℝ => Real.sqrt (1 - x^2) /-- Let $f: [-1, 1] \to \mathbb{R}$ be a continuous function such that \begin{itemize} \item[(i)] $f(x) = \frac{2-x^2}{2} f \left( \frac{x^2}{2-x^2} \right)$ for every $x$ in $[-1, 1]$, \item[(ii)] $f(0) = 1$, and \item[(iii)] $\lim_{x \to 1^-} \frac{f(x)}{\sqrt{1-x}}$ exists and is finite. \end{itemize} Prove that $f$ is unique, and express $f(x)$ in closed form. -/ theorem putnam_2012_a3 (S : Set ℝ) (hS : S = Set.Icc (-1 : ℝ) 1) (fsat : (ℝ β†’ ℝ) β†’ Prop) (hfsat : fsat = fun f : ℝ β†’ ℝ => ContinuousOn f S ∧ (βˆ€ x ∈ S, f x = ((2 - x^2)/2)*f (x^2/(2 - x^2))) ∧ f 0 = 1 ∧ (βˆƒ y : ℝ, leftLim (fun x : ℝ => (f x)/Real.sqrt (1 - x)) 1 = y)) : fsat putnam_2012_a3_solution ∧ βˆ€ f : ℝ β†’ ℝ, fsat f β†’ βˆ€ x ∈ S, f x = putnam_2012_a3_solution x := sorry
bfdb8265cfca8d43
putnam_1997_a3
abbrev putnam_1997_a3_solution : ℝ := sorry -- Real.sqrt (Real.exp 1) /-- Evaluate \begin{gather*} \int_0^\infty \left(x-\frac{x^3}{2}+\frac{x^5}{2\cdot 4}-\frac{x^7}{2\cdot 4\cdot 6}+\cdots\right) \\ \left(1+\frac{x^2}{2^2}+\frac{x^4}{2^2\cdot 4^2}+\frac{x^6}{2^2\cdot 4^2 \cdot 6^2}+\cdots\right)\,dx. \end{gather*} -/ theorem putnam_1997_a3 (series1 series2 : ℝ β†’ ℝ) (hseries1 : series1 = fun x => βˆ‘' n : β„•, (-1)^n * x^(2*n + 1)/(∏ i : Finset.range n, 2 * ((i : ℝ) + 1))) (hseries2 : series2 = fun x => βˆ‘' n : β„•, x^(2*n)/(∏ i : Finset.range n, (2 * ((i : ℝ) + 1))^2)) : Tendsto (fun t => ∫ x in Set.Icc 0 t, series1 x * series2 x) atTop (𝓝 (putnam_1997_a3_solution)) := sorry
023a3b90970ffb65
putnam_2014_a6
abbrev putnam_2014_a6_solution : β„• β†’ β„• := sorry -- (fun n : β„• => n ^ n) /-- Let \( n \) be a positive integer. What is the largest \( k \) for which there exist \( n \times n \) matrices \( M_1, \ldots, M_k \) and \( N_1, \ldots, N_k \) with real entries such that for all \( i \) and \( j \), the matrix product \( M_i N_j \) has a zero entry somewhere on its diagonal if and only if \( i \neq j \)? -/ theorem putnam_2014_a6 (n : β„•) (kex : β„• β†’ Prop) (npos : n > 0) (hkex : βˆ€ k β‰₯ 1, kex k = βˆƒ M N : Fin k β†’ Matrix (Fin n) (Fin n) ℝ, βˆ€ i j : Fin k, ((βˆƒ p : Fin n, (M i * N j) p p = 0) ↔ i β‰  j)) : (putnam_2014_a6_solution n β‰₯ 1 ∧ kex (putnam_2014_a6_solution n)) ∧ (βˆ€ k β‰₯ 1, kex k β†’ k ≀ putnam_2014_a6_solution n) := sorry
c4537e006b5bd630
putnam_2004_a6
theorem putnam_2004_a6 (f : (Set.Icc (0 : ℝ) 1 Γ— Set.Icc (0 : ℝ) 1) β†’ ℝ) (fcont : Continuous f) : (∫ y : Set.Icc (0 : ℝ) 1, (∫ x : Set.Icc (0 : ℝ) 1, f (x, y)) ^ 2) + (∫ x : Set.Icc (0 : ℝ) 1, (∫ y : Set.Icc (0 : ℝ) 1, f (x, y)) ^ 2) ≀ (∫ y : Set.Icc (0 : ℝ) 1, (∫ x : Set.Icc (0 : ℝ) 1, f (x, y))) ^ 2 + (∫ y : Set.Icc (0 : ℝ) 1, (∫ x : Set.Icc (0 : ℝ) 1, (f (x, y)) ^ 2)) := sorry
8500322d6a4a454f
putnam_1973_a3
theorem putnam_1973_a3 (b : β„€ β†’ ℝ) (hb : b = fun (n : β„€) => sInf {k + (n : ℝ)/(k : ℝ) | k > (0 : β„€)}) : βˆ€ n : β„€, n > 0 β†’ floor (b n) = floor (Real.sqrt (4 * n + 1)) := sorry
b0683d5d232f6eb4
putnam_1963_a3
abbrev putnam_1963_a3_solution : (ℝ β†’ ℝ) β†’ β„• β†’ ℝ β†’ ℝ β†’ ℝ := sorry -- fun (f : ℝ β†’ ℝ) (n : β„•) (x : ℝ) (t : ℝ) ↦ (x - t) ^ (n - 1) * (f t) / ((n - 1)! * t ^ n) /-- Find an integral formula (i.e., a function $z$ such that $y(x) = \int_{1}^{x} z(t) dt$) for the solution of the differential equation $$\delta (\delta - 1) (\delta - 2) \cdots (\delta - n + 1) y = f(x)$$ with the initial conditions $y(1) = y'(1) = \cdots = y^{(n-1)}(1) = 0$, where $n \in \mathbb{N}$, $f$ is continuous for all $x \ge 1$, and $\delta$ denotes $x\frac{d}{dx}$. -/ theorem putnam_1963_a3 (P : β„• β†’ (ℝ β†’ ℝ) β†’ (ℝ β†’ ℝ)) (hP : P 0 = id ∧ βˆ€ i y, P (i + 1) y = P i (fun x ↦ x * deriv y x - i * y x)) (n : β„•) (hn : 0 < n) (f y : ℝ β†’ ℝ) (hf : ContinuousOn f (Ici 1)) (hy : ContDiffOn ℝ n y (Ici 1)) : (βˆ€ i < n, deriv^[i] y 1 = 0) ∧ (Ici 1).EqOn (P n y) f ↔ βˆ€ x β‰₯ 1, y x = ∫ t in (1 : ℝ)..x, putnam_1963_a3_solution f n x t := sorry
73704981f558c00d
putnam_1991_a6
theorem putnam_1991_a6 (nabsum : β„• β†’ β„• Γ— (β„• β†’ β„•) β†’ Prop) (agt bge bg1 bg2 : β„• Γ— (β„• β†’ β„•) β†’ Prop) (A g B: β„• β†’ β„•) (hnabsum : βˆ€α΅‰ (n β‰₯ 1) (ab), nabsum n ab ↔ (ab.1 β‰₯ 1 ∧ (βˆ€ i < ab.1, ab.2 i > 0) ∧ (βˆ€ i β‰₯ ab.1, ab.2 i = 0) ∧ (βˆ‘ i : Fin ab.1, ab.2 i) = n)) (hA : βˆ€ n β‰₯ 1, A n = {a | nabsum n a ∧ (βˆ€ i : Fin (a.1 - 2), a.2 i > a.2 (i + 1) + a.2 (i + 2)) ∧ 1 < a.1 β†’ a.2 (a.1 - 2) > a.2 (a.1 - 1)}.encard) (hg : g 0 = 1 ∧ g 1 = 2 ∧ (βˆ€ j β‰₯ 2, g j = g (j - 1) + g (j - 2) + 1)) (hB : βˆ€ n β‰₯ 1, B n = {b | nabsum n b ∧ (βˆ€ i : Fin (b.1 - 1), b.2 i β‰₯ b.2 (i + 1)) ∧ (βˆ€ i : Fin b.1, βˆƒ j : β„•, b.2 i = g j) ∧ (βˆƒ k : β„•, b.2 0 = g k ∧ (βˆ€ j ≀ k, βˆƒ i : Fin b.1, b.2 i = g j))}.encard) : βˆ€ n β‰₯ 1, (A n) = (B n) := sorry
1815b5f2f0f92c84
putnam_1986_a2
abbrev putnam_1986_a2_solution : β„• := sorry -- 3 /-- What is the units (i.e., rightmost) digit of \[ \left\lfloor \frac{10^{20000}}{10^{100}+3}\right\rfloor ? \] -/ theorem putnam_1986_a2 : (Nat.floor ((10 ^ 20000 : ℝ) / (10 ^ 100 + 3)) % 10 = putnam_1986_a2_solution) := sorry
fb3e62a24123156a
putnam_1996_a2
abbrev putnam_1996_a2_solution : (EuclideanSpace ℝ (Fin 2)) β†’ (EuclideanSpace ℝ (Fin 2)) β†’ Set (EuclideanSpace ℝ (Fin 2)) := sorry -- (fun O1 O2 : EuclideanSpace ℝ (Fin 2) => {p : EuclideanSpace ℝ (Fin 2) | dist p (midpoint ℝ O1 O2) β‰₯ 1 ∧ dist p (midpoint ℝ O1 O2) ≀ 2}) /-- Let $C_1$ and $C_2$ be circles whose centers are $10$ units apart, and whose radii are $1$ and $3$. Find, with proof, the locus of all points $M$ for which there exist points $X$ on $C_1$ and $Y$ on $C_2$ such that $M$ is the midpoint of the line segment $XY$. -/ theorem putnam_1996_a2 (O1 O2 : EuclideanSpace ℝ (Fin 2)) (C1 C2 : Set (EuclideanSpace ℝ (Fin 2))) (hC1 : C1 = sphere O1 1) (hC2 : C2 = sphere O2 3) (hO1O2 : dist O1 O2 = 10) : {M : EuclideanSpace ℝ (Fin 2) | βˆƒ X Y, X ∈ C1 ∧ Y ∈ C2 ∧ M = midpoint ℝ X Y} = putnam_1996_a2_solution O1 O2 := sorry
fc130f2776bfe01e
putnam_2013_a2
theorem putnam_2013_a2 (S : Set β„€) (hS : S = {n : β„€ | n > 0 ∧ Β¬βˆƒ m : β„€, m ^ 2 = n}) (P : β„€ β†’ List β„€ β†’ Prop) (hP : βˆ€ n a, P n a ↔ a.length > 0 ∧ n < a[0]! ∧ (βˆƒ m : β„€, m ^ 2 = n * a.prod) ∧ (βˆ€ i : Fin (a.length - 1), a[i] < a[i+(1:β„•)])) (T : β„€ β†’ Set β„€) (hT : T = fun n : β„€ => {m : β„€ | βˆƒ a : List β„€, P n a ∧ a[a.length - 1]! = m}) (f : β„€ β†’ β„€) (hf : βˆ€ n ∈ S, ((βˆƒ r ∈ T n, f n = r) ∧ βˆ€ r ∈ T n, f n ≀ r)) : InjOn f S := sorry
619904f5c957907e
putnam_2003_a2
theorem putnam_2003_a2 (n : β„•) (hn : 0 < n) (a b : Fin n β†’ ℝ) (abnneg : βˆ€ i, a i β‰₯ 0 ∧ b i β‰₯ 0) : (∏ i, a i) ^ ((1 : ℝ) / n) + (∏ i, b i) ^ ((1 : ℝ) / n) ≀ (∏ i, (a i + b i)) ^ ((1 : ℝ) / n) := sorry
a4617d509a48d8bf
putnam_1989_b1
abbrev putnam_1989_b1_solution : β„€ Γ— β„€ Γ— β„€ Γ— β„€ := sorry -- (4, 2, -5, 3) /-- A dart, thrown at random, hits a square target. Assuming that any two parts of the target of equal area are equally likely to be hit, find the probability that the point hit is nearer to the center than to any edge. Express your answer in the form $(a\sqrt{b}+c)/d$, where $a$, $b$, $c$, $d$ are integers and $b$, $d$ are positive. -/ theorem putnam_1989_b1 (square Scloser perimeter: Set (EuclideanSpace ℝ (Fin 2))) (center : EuclideanSpace ℝ (Fin 2)) (square_def : square = {p | βˆ€ i : Fin 2, p i ∈ Set.Icc 0 1}) (perimeter_def : perimeter = {p ∈ square | p 0 = 0 ∨ p 0 = 1 ∨ p 1 = 0 ∨ p 1 = 1}) (center_def : center = (fun i : Fin 2 => 1 / 2)) (hScloser : Scloser = {p ∈ square | βˆ€ q ∈ perimeter, dist p center < dist p q}) : let (a, b, c, d) := putnam_1989_b1_solution; b > 0 ∧ d > 0 ∧ (Β¬βˆƒ n : β„€, n^2 = b) ∧ (volume Scloser).toReal / (volume square).toReal = (a * Real.sqrt b + c) / d := sorry
c4b8a6b60b2360cb
putnam_2000_a4
theorem putnam_2000_a4 : βˆƒ y : ℝ, Tendsto (fun B : ℝ => ∫ x in Set.Ioo 0 B, Real.sin x * Real.sin (x ^ 2)) atTop (𝓝 y) := sorry
547e3ad75b9ab1a4
putnam_2010_a4
theorem putnam_2010_a4 : βˆ€ n : β„•, n > 0 β†’ Β¬Nat.Prime (10^10^10^n + 10^10^n + 10^n - 1) := sorry
67bf2958bcb42226
putnam_1967_a1
theorem putnam_1967_a1 (n : β„•) (hn : n > 0) (a : Set.Icc 1 n β†’ ℝ) (f : ℝ β†’ ℝ) (hf : f = (fun x : ℝ => βˆ‘ i : Set.Icc 1 n, a i * Real.sin (i * x))) (flesin : βˆ€ x : ℝ, abs (f x) ≀ abs (Real.sin x)) : abs (βˆ‘ i : Set.Icc 1 n, i * a i) ≀ 1 := sorry
3ce146116b935699
putnam_1977_a1
abbrev putnam_1977_a1_solution : ℝ := sorry -- -7 / 8 /-- Show that if four distinct points of the curve $y = 2x^4 + 7x^3 + 3x - 5$ are collinear, then their average $x$-coordinate is some constant $k$. Find $k$. -/ theorem putnam_1977_a1 (y : ℝ β†’ ℝ) (hy : y = fun x ↦ 2 * x ^ 4 + 7 * x ^ 3 + 3 * x - 5) (S : Finset ℝ) (hS : S.card = 4) : (Collinear ℝ {P : Fin 2 β†’ ℝ | P 0 ∈ S ∧ P 1 = y (P 0)} β†’ (βˆ‘ x in S, x) / 4 = putnam_1977_a1_solution) := sorry
c520a08077a2b926
putnam_1978_b2
abbrev putnam_1978_b2_solution : β„š := sorry -- 7 / 4 /-- Find \[ \sum_{i=1}^{\infty} \sum_{j=1}^{\infty} \frac{1}{i^2j + 2ij + ij^2}. \] -/ theorem putnam_1978_b2 : (βˆ‘' i : β„•+, βˆ‘' j : β„•+, (1 : β„š) / (i ^ 2 * j + 2 * i * j + i * j ^ 2) = putnam_1978_b2_solution) := sorry
9abff58508c044d4
putnam_1995_a4
theorem putnam_1995_a4 (n : β„•) (hn : n > 0) (necklace : Fin n β†’ β„€) (hnecklacesum : βˆ‘ i : Fin n, necklace i = n - 1) : βˆƒ cut, βˆ€ k, βˆ‘ i : {j : Fin n | j.1 ≀ k}, necklace (cut + i) ≀ k := sorry
06a2770f00322a73
putnam_1968_b2
theorem putnam_1968_b2 {G : Type*} [Group G] (hG : Finite G) (A : Set G) (hA : A.ncard > (Nat.card G : β„š)/2) : βˆ€ g : G, βˆƒ x ∈ A, βˆƒ y ∈ A, g = x * y := sorry
c341f40734ff7d56
putnam_1985_a4
abbrev putnam_1985_a4_solution : Set (Fin 100) := sorry -- {87} /-- Define a sequence $\{a_i\}$ by $a_1=3$ and $a_{i+1}=3^{a_i}$ for $i \geq 1$. Which integers between $00$ and $99$ inclusive occur as the last two digits in the decimal expansion of infinitely many $a_i$? -/ theorem putnam_1985_a4 (a : β„• β†’ β„•) (ha1 : a 1 = 3) (ha : βˆ€ i β‰₯ 1, a (i + 1) = 3 ^ a i) : {k : Fin 100 | βˆ€ N : β„•, βˆƒ i β‰₯ N, a i % 100 = k} = putnam_1985_a4_solution := sorry
ea7f31b1aadfb47a
putnam_2018_b3
abbrev putnam_2018_b3_solution : Set β„• := sorry -- {2^2, 2^4, 2^16, 2^256} /-- Find all positive integers $n < 10^{100}$ for which simultaneously $n$ divides $2^n$, $n-1$ divides $2^n-1$, and $n-2$ divides $2^n - 2$. -/ theorem putnam_2018_b3 (n : β„•) (hn : 0 < n) : (n < 10^100 ∧ ((n : β„€) ∣ (2^n : β„€) ∧ (n - 1 : β„€) ∣ (2^n - 1 : β„€) ∧ (n - 2 : β„€) ∣ (2^n - 2 : β„€))) ↔ n ∈ putnam_2018_b3_solution := sorry
bf804d431255cba5
putnam_2008_b3
abbrev putnam_2008_b3_solution : ℝ := sorry -- Real.sqrt 2 / 2 /-- What is the largest possible radius of a circle contained in a $4$-dimensional hypercube of side length $1$? -/ theorem putnam_2008_b3 (H : Set (EuclideanSpace ℝ (Fin 4))) (H_def : H = {P : Fin 4 β†’ ℝ | βˆ€ i : Fin 4, |P i| ≀ 1 / 2}) (contains : ℝ β†’ Prop) (contains_def : βˆ€ r, contains r ↔ βˆƒα΅‰ (A : AffineSubspace ℝ (EuclideanSpace ℝ (Fin 4))) (C ∈ A), Module.finrank ℝ A.direction = 2 ∧ sphere C r ∩ A βŠ† H) : IsGreatest contains putnam_2008_b3_solution := sorry
e79c95a0c0cf7ce7
putnam_1980_b6
theorem putnam_1980_b6 (G : β„€ Γ— β„€ β†’ β„š) (hG : βˆ€ d n : β„•, d ≀ n β†’ (d = 1 β†’ G (d, n) = 1/(n : β„š)) ∧ (d > 1 β†’ G (d, n) = (d/(n : β„š))*βˆ‘ i in Finset.Icc d n, G ((d : β„€) - 1, (i : β„€) - 1))) : βˆ€ d p : β„•, 1 < d ∧ d ≀ p ∧ Prime p β†’ Β¬p ∣ (G (d, p)).den := sorry
46eacf38ed14cb7c
putnam_2005_b6
theorem putnam_2005_b6 (n : β„•) (v : Equiv.Perm (Fin n) β†’ β„•) (npos : n β‰₯ 1) (hv : βˆ€ p : Equiv.Perm (Fin n), v p = Set.encard {i : Fin n | p i = i}) : (βˆ‘ p : Equiv.Perm (Fin n), (Equiv.Perm.signAux p : β„€) / (v p + 1 : ℝ)) = (-1) ^ (n + 1) * (n / (n + 1 : ℝ)) := sorry
0cdb99c50d245314
putnam_2015_b6
abbrev putnam_2015_b6_solution : ℝ := sorry -- Real.pi ^ 2 / 16 /-- For each positive integer $k$, let $A(k)$ be the number of odd divisors of $k$ in the interval $[1,\sqrt{2k})$. Evaluate $\sum_{k=1}^\infty (-1)^{k-1}\frac{A(k)}{k}$. -/ theorem putnam_2015_b6 (A : β„• β†’ β„•) (hA : βˆ€ k > 0, A k = {j : β„• | Odd j ∧ j ∣ k ∧ j < Real.sqrt (2 * k)}.encard) : Tendsto (fun K : β„• ↦ βˆ‘ k in Finset.Icc 1 K, (-1 : ℝ) ^ ((k : ℝ) - 1) * (A k / (k : ℝ))) atTop (𝓝 putnam_2015_b6_solution) := sorry
839a9f57b374c516
putnam_1962_b3
theorem putnam_1962_b3 (S : Set (EuclideanSpace ℝ (Fin 2))) (hS : Convex ℝ S ∧ 0 ∈ S) (htopo : (0 ∈ interior S) ∨ IsClosed S) (hray : βˆ€ P : EuclideanSpace ℝ (Fin 2), P β‰  0 β†’ βˆƒ Q : EuclideanSpace ℝ (Fin 2), SameRay ℝ P Q ∧ Q βˆ‰ S) : Bornology.IsBounded S := sorry
6388dbd795a4f407
putnam_1972_b3
theorem putnam_1972_b3 (G : Type*) [Group G] (A B : G) (hab : A * B * A = B * A^2 * B ∧ A^3 = 1 ∧ (βˆƒ n : β„€, n > 0 ∧ B^(2*n - 1) = 1)) : B = 1 := sorry
b205109bad09b688
putnam_1988_a1
abbrev putnam_1988_a1_solution : ℝ := sorry -- 6 /-- Let $R$ be the region consisting of the points $(x,y)$ of the cartesian plane satisfying both $|x|-|y| \leq 1$ and $|y| \leq 1$. Find the area of $R$. -/ theorem putnam_1988_a1 (R : Set (Fin 2 β†’ ℝ)) (hR : R = {p | |p 0| - |p 1| ≀ 1 ∧ |p 1| ≀ 1}) : (volume R).toReal = putnam_1988_a1_solution := sorry
8b20e82014063e18
putnam_2020_a6
abbrev putnam_2020_a6_solution : ℝ := sorry -- Real.pi / 4 /-- For a positive integer $N$, let $f_N$ be the function defined by \[ f_N(x) = \sum_{n=0}^N \frac{N+1/2-n}{(N+1)(2n+1)} \sin((2n+1)x). \] Determine the smallest constant $M$ such that $f_N(x) \leq M$ for all $N$ and all real $x$. -/ theorem putnam_2020_a6 (f : β„€ β†’ (ℝ β†’ ℝ)) (hf : f = fun N : β„€ => fun x : ℝ => βˆ‘ n in Finset.Icc 0 N, (N + 1/2 - n)/((N + 1)*(2*n + 1)) * Real.sin ((2*n + 1)*x)) : putnam_2020_a6_solution = sSup {y | βˆƒα΅‰ (N > 0) (x : ℝ), y = f N x} := sorry
41004573a19b5c80
putnam_1997_b2
theorem putnam_1997_b2 (f g : ℝ β†’ ℝ) (hg : βˆ€ x : ℝ, g x β‰₯ 0) (hfderiv1 : ContDiff ℝ 1 f) (hfderiv2 : Differentiable ℝ (deriv f)) (hfg : βˆ€ x : ℝ, f x + iteratedDeriv 2 f x = -x * g x * deriv f x) : IsBounded (range (fun x => |f x|)) := sorry
b0c4e241cf0ed0c5
putnam_1987_b2
theorem putnam_1987_b2 (r s t : β„•) (hsum : r + s ≀ t) : (βˆ‘ i : Finset.range (s + 1), (choose s i : β„š) / (choose t (r + i)) = ((t + 1) : β„š) / ((t + 1 - s) * choose (t - s) r)) := sorry
7d8b12efa243a2df
putnam_1969_a2
theorem putnam_1969_a2 (D : (n : β„•) β†’ Matrix (Fin n) (Fin n) ℝ) (hD : D = fun (n : β„•) => Ξ» (i : Fin n) (j : Fin n) => |(i : ℝ) - (j : ℝ)| ) : βˆ€ n, n β‰₯ 2 β†’ (D n).det = (-1)^((n : β„€)-1) * ((n : β„€)-1) * 2^((n : β„€)-2) := sorry
cd5ce63c0d77a487
putnam_1979_a2
abbrev putnam_1979_a2_solution : ℝ β†’ Prop := sorry -- fun k : ℝ => k β‰₯ 0 /-- For which real numbers $k$ does there exist a continuous function $f : \mathbb{R} \to \mathbb{R}$ such that $f(f(x)) = kx^9$ for all real $x$? -/ theorem putnam_1979_a2 : βˆ€ k : ℝ, (βˆƒ f : ℝ β†’ ℝ, Continuous f ∧ βˆ€ x : ℝ, f (f x) = k*x^9) ↔ putnam_1979_a2_solution k := sorry
707705262d9f6bc9
putnam_1994_b4
theorem putnam_1994_b4 (matgcd : Matrix (Fin 2) (Fin 2) β„€ β†’ β„€) (A : Matrix (Fin 2) (Fin 2) β„€) (d : β„• β†’ β„€) (hmatgcd : βˆ€ M, matgcd M = Int.gcd (Int.gcd (Int.gcd (M 0 0) (M 0 1)) (M 1 0)) (M 1 1)) (hA : A 0 0 = 3 ∧ A 0 1 = 2 ∧ A 1 0 = 4 ∧ A 1 1 = 3) (hd : βˆ€ n β‰₯ 1, d n = matgcd (A ^ n - 1)) : Tendsto d atTop atTop := sorry
edfba96dbbe691ff
putnam_2011_b4
theorem putnam_2011_b4 (games : Fin 2011 β†’ Fin 2011 β†’ Bool) (T W : Matrix (Fin 2011) (Fin 2011) β„‚) (hT : T = (fun p1 p2 => ({g | games g p1 = games g p2}.ncard : β„‚))) (hW : W = (fun p1 p2 => ({g | games g p1 ∧ !games g p2}.ncard - {g | !games g p1 ∧ games g p2}.ncard : β„‚))) : βˆƒ n : β„•, (T + Complex.I β€’ W).det = n ∧ (2 ^ 2010) ∣ n := sorry
2db5d4e5012aa7e5
putnam_2001_b4
abbrev putnam_2001_b4_solution : Prop := sorry -- True /-- Let $S$ denote the set of rational numbers different from $\{-1,0,1\}$. Define $f:S\rightarrow S$ by $f(x)=x-1/x$. Prove or disprove that \[\bigcap_{n=1}^\infty f^{(n)}(S) = \emptyset,\] where $f^{(n)}$ denotes $f$ composed with itself $n$ times. -/ theorem putnam_2001_b4 (S : Set β„š) (hS : S = univ \ {-1, 0, 1}) (f : S β†’ S) (hf : βˆ€ x : S, f x = x - 1 / (x : β„š)) : β‹‚ n ∈ Ici 1, f^[n] '' univ = βˆ… ↔ putnam_2001_b4_solution := sorry
612d88fa19e431c1
putnam_1976_b1
abbrev putnam_1976_b1_solution : β„• Γ— β„• := sorry -- (4, 1) /-- Find $$\lim_{n \to \infty} \frac{1}{n} \sum_{k=1}^{n}\left(\left\lfloor \frac{2n}{k} \right\rfloor - 2\left\lfloor \frac{n}{k} \right\rfloor\right).$$ Your answer should be in the form $\ln(a) - b$, where $a$ and $b$ are positive integers. -/ theorem putnam_1976_b1 : Tendsto (fun n : β„• => ((1 : ℝ)/n)*βˆ‘ k in Finset.Icc (1 : β„€) n, (Int.floor ((2*n)/k) - 2*Int.floor (n/k))) atTop (𝓝 (Real.log putnam_1976_b1_solution.1 - putnam_1976_b1_solution.2)) := sorry
12148cb024c95406
putnam_1966_b1
theorem putnam_1966_b1 (n : β„•) (hn : n β‰₯ 3) (L : ZMod n β†’ (EuclideanSpace ℝ (Fin 2))) (hsq : βˆ€ i : ZMod n, L i 0 ∈ Set.Icc 0 1 ∧ L i 1 ∈ Set.Icc 0 1) (hnoncol : βˆ€ i j k : ZMod n, i β‰  j ∧ j β‰  k ∧ k β‰  i β†’ Β¬Collinear ℝ {L i, L j, L k}) (hconvex : βˆ€ i : ZMod n, segment ℝ (L i) (L (i + 1)) ∩ interior (convexHull ℝ {L j | j : ZMod n}) = βˆ…) : βˆ‘ i : Fin n, (dist (L i) (L (i + 1)))^2 ≀ 4 := sorry
ea44d5a94a362efa
putnam_2024_a4
abbrev putnam_2024_a4_solution : Set β„• := sorry --{7} /-- Find all primes $p > 5$ for which there exists an integer $a$ and an integer $r$ satisfying $1 \le r \le p - 1$ with the following property: the sequence $1, a, a^2, ..., a^{p-5}$ can be rearranged to form a sequence $b_0, ..., b_{p-5}$ such that $b_n - b_{n-1} - r$ is divisible by $p$ for $1 \le n \le p - 5$. -/ theorem putnam_2024_a4 : {p : β„• | p.Prime ∧ 5 < p ∧ βˆƒ a r : β„€, 1 ≀ r ∧ r ≀ p - 1 ∧ βˆƒ e : β„• β†’ β„•, Set.BijOn e (Set.Icc 0 (p - 5 : β„•)) (Set.Icc 0 (p - 5 : β„•)) ∧ βˆ€ n, 1 ≀ n ∧ n ≀ (p - 5 : β„•) β†’ (p : β„€) ∣ a ^ (e n : β„•) - a ^ (e (n - 1) : β„•) - r} = putnam_2024_a4_solution := sorry
a7409229837cb472
putnam_2009_a3
abbrev putnam_2009_a3_solution : ℝ := sorry -- 0 /-- Let $d_n$ be the determinant of the $n \times n$ matrix whose entries, from left to right and then from top to bottom, are $\cos 1, \cos 2, \dots, \cos n^2$. (For example,\[ d_3 = \left|\begin{matrix} \cos 1 & \cos 2 & \cos 3 \\ \cos 4 & \cos 5 & \cos 6 \\ \cos 7 & \cos 8 & \cos 9 \end{matrix} \right|. \]The argument of $\cos$ is always in radians, not degrees.) Evaluate $\lim_{n\to\infty} d_n$. -/ theorem putnam_2009_a3 (cos_matrix : (n : β„•) β†’ Matrix (Fin n) (Fin n) ℝ) (hM : βˆ€ n : β„•, βˆ€ i j : Fin n, (cos_matrix n) i j = Real.cos (1 + n * i + j)) : Tendsto (fun n => (cos_matrix n).det) atTop (𝓝 putnam_2009_a3_solution) := sorry
16bcb3911e43c1bf
putnam_2019_a3
abbrev putnam_2019_a3_solution : ℝ := sorry -- 2019^(-(1:ℝ)/2019) /-- Given real numbers $b_0, b_1, \dots, b_{2019}$ with $b_{2019} \neq 0$, let $z_1,z_2,\dots,z_{2019}$ be the roots in the complex plane of the polynomial \[ P(z) = \sum_{k=0}^{2019} b_k z^k. \] Let $\mu = (|z_1| + \cdots + |z_{2019}|)/2019$ be the average of the distances from $z_1,z_2,\dots,z_{2019}$ to the origin. Determine the largest constant $M$ such that $\mu \geq M$ for all choices of $b_0,b_1,\dots, b_{2019}$ that satisfy \[ 1 \leq b_0 < b_1 < b_2 < \cdots < b_{2019} \leq 2019. \] -/ theorem putnam_2019_a3 (v : Polynomial β„‚ β†’ Prop) (hv : v = fun b => b.degree = 2019 ∧ 1 ≀ (b.coeff 0).re ∧ (b.coeff 2019).re ≀ 2019 ∧ (βˆ€ i : Fin 2020, (b.coeff i).im = 0) ∧ (βˆ€ i : Fin 2019, (b.coeff i).re < (b.coeff (i + 1)).re)) (ΞΌ : Polynomial β„‚ β†’ ℝ) (hΞΌ : ΞΌ = fun b => (Multiset.map (fun Ο‰ : β„‚ => β€–Ο‰β€–) (Polynomial.roots b)).sum/2019) : IsGreatest {M : ℝ | βˆ€ b, v b β†’ ΞΌ b β‰₯ M} putnam_2019_a3_solution := sorry
c0caf67c7210190b
putnam_2022_a1
abbrev putnam_2022_a1_solution : Set (ℝ Γ— ℝ) := sorry -- {(a, b) | (a = 0 ∧ b = 0) ∨ 1 ≀ |a| ∨ (0 < |a| ∧ |a| < 1 ∧ letI rm := (1 - √(1 - a ^ 2)) / a; letI rp := (1 + √(1 - a ^ 2)) / a; (b < Real.log (1 + rm ^ 2) - a * rm ∨ b > Real.log (1 + rp ^ 2) - a * rp))} /-- Determine all ordered pairs of real numbers $(a,b)$ such that the line $y = ax+b$ intersects the curve $y = \ln(1+x^2)$ in exactly one point. -/ theorem putnam_2022_a1 : {(a, b) | βˆƒ! x : ℝ, a * x + b = Real.log (1 + x^2)} = putnam_2022_a1_solution := sorry
e5d6a4cd681e259f
putnam_2000_b5
theorem putnam_2000_b5 (S : β„• β†’ Set β„€) (hSfin : βˆ€ n, Set.Finite (S n)) (hSpos : βˆ€ n, βˆ€ s ∈ S n, s > 0) (hSdef : βˆ€ n, βˆ€ a, a ∈ S (n + 1) ↔ Xor' (a - 1 ∈ S n) (a ∈ S n)) : (βˆ€ n, βˆƒ N β‰₯ n, S N = S 0 βˆͺ {M : β„€ | M - N ∈ S 0}) := sorry
8ec0022a4579ff4a
putnam_2010_b5
abbrev putnam_2010_b5_solution : Prop := sorry -- False /-- Is there a strictly increasing function $f: \mathbb{R} \to \mathbb{R}$ such that $f'(x) = f(f(x))$ for all $x$? -/ theorem putnam_2010_b5 : (βˆƒ f : ℝ β†’ ℝ, StrictMono f ∧ Differentiable ℝ f ∧ (βˆ€ x : ℝ, deriv f x = f (f x))) ↔ putnam_2010_b5_solution := sorry
10fb3d8ff1be8a64
putnam_1978_a3
abbrev putnam_1978_a3_solution : β„• := sorry -- 2 /-- Let $p(x) = 2(x^6 + 1) + 4(x^5 + x) + 3(x^4 + x^2) + 5x^3$. For $k$ with $0 < k < 5$, let \[ I_k = \int_0^{\infty} \frac{x^k}{p(x)} \, dx. \] For which $k$ is $I_k$ smallest? -/ theorem putnam_1978_a3 (p : Polynomial ℝ) (hp : p = 2 * (X ^ 6 + 1) + 4 * (X ^ 5 + X) + 3 * (X ^ 4 + X ^ 2) + 5 * X ^ 3) (I : β„• β†’ ℝ) (hI : I = fun k ↦ ∫ x in Ioi 0, x ^ k / p.eval x) : IsLeast {y | βˆƒ k ∈ Ioo 0 5, I k = y} putnam_1978_a3_solution := sorry
6dfa01bb29a42f75
putnam_1985_b5
abbrev putnam_1985_b5_solution : ℝ := sorry -- sqrt (Real.pi / 1985) * exp (-3970) /-- Evaluate $\int_0^\infty t^{-1/2}e^{-1985(t+t^{-1})}\,dt$. You may assume that $\int_{-\infty}^\infty e^{-x^2}\,dx = \sqrt{\pi}$. -/ theorem putnam_1985_b5 (fact : ∫ x in univ, exp (- x ^ 2) = sqrt (Real.pi)) : (∫ t in Set.Ioi 0, t ^ (- (1 : ℝ) / 2) * exp (-1985 * (t + t ^ (-(1 : ℝ)))) = putnam_1985_b5_solution) := sorry
a3d6513e2e95d266
putnam_1968_a3
theorem putnam_1968_a3 (Ξ± : Type*) [Finite Ξ±] : βˆƒ (n : β„•) (s : Fin (2 ^ n) β†’ Set Ξ±), s 0 = βˆ… ∧ (βˆ€ t, βˆƒ! i, s i = t) ∧ (βˆ€ i, i + 1 < 2 ^ n β†’ (s i βˆ† s (i + 1)).ncard = 1) := sorry
669b05b58514fda1
putnam_1992_b1
abbrev putnam_1992_b1_solution : β„• β†’ β„€ := sorry -- fun n ↦ 2 * n - 3 /-- Let $S$ be a set of $n$ distinct real numbers. Let $A_S$ be the set of numbers that occur as averages of two distinct elements of $S$. For a given $n \geq 2$, what is the smallest possible number of elements in $A_S$? -/ theorem putnam_1992_b1 (n : β„•) (hn : n β‰₯ 2) (A : Finset ℝ β†’ Set ℝ) (hA : A = fun S ↦ {x | βˆƒ a ∈ S, βˆƒ b ∈ S, a β‰  b ∧ (a + b) / 2 = x}) : IsLeast {k : β„€ | βˆƒ S : Finset ℝ, S.card = n ∧ k = (A S).ncard} (putnam_1992_b1_solution n) := sorry
ae38b0d5b9256206
putnam_2018_a2
abbrev putnam_2018_a2_solution : β„• β†’ ℝ := sorry -- (fun n : β„• => if n = 1 then 1 else -1) /-- Let \( S_1, S_2, \ldots, S_{2^n-1} \) be the nonempty subsets of \( \{1, 2, \ldots, n\} \) in some order, and let \( M \) be the \( (2^n - 1) \times (2^n - 1) \) matrix whose \((i, j)\) entry is $m_{ij} = \begin{cases} 0 & \text{if } S_i \cap S_j = \emptyset; \\ 1 & \text{otherwise}. \end{cases} $ Calculate the determinant of \( M \). -/ theorem putnam_2018_a2 (n : β„•) (S : Fin (2 ^ n - 1) β†’ Set β„•) (M : Matrix (Fin (2 ^ n - 1)) (Fin (2 ^ n - 1)) ℝ) (npos : n β‰₯ 1) (hS : Set.range S = (Set.Icc 1 n).powerset \ {βˆ…}) (hM : βˆ€ i j, M i j = if (S i ∩ S j = βˆ…) = True then 0 else 1) : M.det = putnam_2018_a2_solution n := sorry
092833985e3e20a9
putnam_1970_b4
theorem putnam_1970_b4 (x : ℝ β†’ ℝ) (hdiff : DifferentiableOn ℝ x (Set.Icc 0 1) ∧ DifferentiableOn ℝ (deriv x) (Set.Icc 0 1)) (hx : x 1 - x 0 = 1) (hv : deriv x 0 = 0 ∧ deriv x 1 = 0) (hs : βˆ€ t ∈ Set.Ioo 0 1, |deriv x t| ≀ 3/2) : βˆƒ t ∈ Set.Icc 0 1, |(deriv (deriv x)) t| β‰₯ 9/2 := sorry
6a21dc92728d8dad
putnam_2007_b1
theorem putnam_2007_b1 (f : Polynomial β„€) (hf : βˆ€ n : β„•, f.coeff n β‰₯ 0) (hfnconst : βˆƒ n : β„•, n > 0 ∧ f.coeff n > 0) (n : β„€) (hn : n > 0) : f.eval n ∣ f.eval (f.eval n + 1) ↔ n = 1 := sorry
79279b52f6d8e15f
putnam_2017_b1
theorem putnam_2017_b1 (lines : Set (Set (Fin 2 β†’ ℝ))) (L1 L2 : Set (Fin 2 β†’ ℝ)) (L1L2lines : L1 ∈ lines ∧ L2 ∈ lines) (L1L2distinct : L1 β‰  L2) (hlines : lines = {L | βˆƒ v w : Fin 2 β†’ ℝ, w β‰  0 ∧ L = {p | βˆƒ t : ℝ, p = v + t β€’ w}}) : L1 ∩ L2 β‰  βˆ… ↔ (βˆ€ lambda : ℝ, lambda β‰  0 β†’ βˆ€ P, (P βˆ‰ L1 ∧ P βˆ‰ L2) β†’ βˆƒ A1 A2, A1 ∈ L1 ∧ A2 ∈ L2 ∧ (A2 - P = lambda β€’ (A1 - P))) := sorry
652348a1a8a3be26
putnam_1973_b2
theorem putnam_1973_b2 (z : β„‚) (hzrat : βˆƒ q1 q2 : β„š, z.re = q1 ∧ z.im = q2) (hznorm : β€–zβ€– = 1) : βˆ€ n : β„€, βˆƒ q : β„š, β€–z^(2*n) - 1β€– = q := sorry
a1f56ebd4063f7ff