n, a, b = map(int, input().split())
mod = 10**9 + 7

modinv_table_a = [-1] * (a+1)
modinv_table_a[1] = 1
for i in range(2, a+1):
    modinv_table_a[i] = (-modinv_table_a[mod % i] * (mod // i)) % mod

modinv_table_b = [-1] * (b+1)
modinv_table_b[1] = 1
for i in range(2, b+1):
    modinv_table_b[i] = (-modinv_table_b[mod % i] * (mod // i)) % mod

def binomial_coefficients_a(n, k):
    ans = 1
    for i in range(k):
        ans *= n-i
        ans *= modinv_table_a[i + 1]
        ans %= mod
    return ans

def binomial_coefficients_b(n, k):
    ans = 1
    for i in range(k):
        ans *= n-i
        ans *= modinv_table_b[i + 1]
        ans %= mod
    return ans

res = (pow(2,n,mod)-binomial_coefficients_a(n,a)-binomial_coefficients_b(n,b)-1)%mod
print(res if res >= 0 else res+mod) n, a, b = map(int, input().split()) n map(int, input().split()) map int input().split() ().split () input split a b mod = 10**9 + 7 mod 10**9 + 7 10**9 10 9 7 modinv_table_a = [-1] * (a+1) modinv_table_a [-1] * (a+1) [-1] -1 a+1 a 1 modinv_table_a[1] = 1 modinv_table_a[1] modinv_table_a 1 1 for i in range(2, a+1):
    modinv_table_a[i] = (-modinv_table_a[mod % i] * (mod // i)) % mod i range(2, a+1) range 2 a+1 a 1 modinv_table_a[i] = (-modinv_table_a[mod % i] * (mod // i)) % mod modinv_table_a[i] modinv_table_a i (-modinv_table_a[mod % i] * (mod // i)) % mod -modinv_table_a[mod % i] * (mod // i) -modinv_table_a[mod % i] modinv_table_a[mod % i] modinv_table_a mod % i mod i mod // i mod i mod modinv_table_b = [-1] * (b+1) modinv_table_b [-1] * (b+1) [-1] -1 b+1 b 1 modinv_table_b[1] = 1 modinv_table_b[1] modinv_table_b 1 1 for i in range(2, b+1):
    modinv_table_b[i] = (-modinv_table_b[mod % i] * (mod // i)) % mod i range(2, b+1) range 2 b+1 b 1 modinv_table_b[i] = (-modinv_table_b[mod % i] * (mod // i)) % mod modinv_table_b[i] modinv_table_b i (-modinv_table_b[mod % i] * (mod // i)) % mod -modinv_table_b[mod % i] * (mod // i) -modinv_table_b[mod % i] modinv_table_b[mod % i] modinv_table_b mod % i mod i mod // i mod i mod def binomial_coefficients_a(n, k):
    ans = 1
    for i in range(k):
        ans *= n-i
        ans *= modinv_table_a[i + 1]
        ans %= mod
    return ans binomial_coefficients_a ans = 1 ans 1 for i in range(k):
        ans *= n-i
        ans *= modinv_table_a[i + 1]
        ans %= mod
     i range(k) range k ans *= n-i ans n-i n i ans *= modinv_table_a[i + 1] ans modinv_table_a[i + 1] modinv_table_a i + 1 i 1 ans %= mod ans mod return ans ans n n k k def binomial_coefficients_b(n, k):
    ans = 1
    for i in range(k):
        ans *= n-i
        ans *= modinv_table_b[i + 1]
        ans %= mod
    return ans binomial_coefficients_b ans = 1 ans 1 for i in range(k):
        ans *= n-i
        ans *= modinv_table_b[i + 1]
        ans %= mod
     i range(k) range k ans *= n-i ans n-i n i ans *= modinv_table_b[i + 1] ans modinv_table_b[i + 1] modinv_table_b i + 1 i 1 ans %= mod ans mod return ans ans n n k k res = (pow(2,n,mod)-binomial_coefficients_a(n,a)-binomial_coefficients_b(n,b)-1)%mod res (pow(2,n,mod)-binomial_coefficients_a(n,a)-binomial_coefficients_b(n,b)-1)%mod pow(2,n,mod)-binomial_coefficients_a(n,a)-binomial_coefficients_b(n,b)-1 pow(2,n,mod)-binomial_coefficients_a(n,a)-binomial_coefficients_b(n,b) pow(2,n,mod)-binomial_coefficients_a(n,a) pow(2,n,mod) pow 2 n mod binomial_coefficients_a(n,a) binomial_coefficients_a n a binomial_coefficients_b(n,b) binomial_coefficients_b n b 1 mod print(res if res >= 0 else res+mod) print res if res >= 0 else res+mod res >= 0 res 0 res res+mod res mod def binomial_coefficients_b(n, k):
    ans = 1
    for i in range(k):
        ans *= n-i
        ans *= modinv_table_b[i + 1]
        ans %= mod
    return ans def binomial_coefficients_b(n, k):
    ans = 1
    for i in range(k):
        ans *= n-i
        ans *= modinv_table_b[i + 1]
        ans %= mod
    return ans binomial_coefficients_b res = (pow(2,n,mod)-binomial_coefficients_a(n,a)-binomial_coefficients_b(n,b)-1)%mod (pow(2,n,mod)-binomial_coefficients_a(n,a)-binomial_coefficients_b(n,b)-1)%mod res a, b = map(int, input().split()) map(int, input().split()) a mod = 10**9 + 7 10**9 + 7 mod modinv_table_b = [-1] * (b+1) [-1] * (b+1) modinv_table_b n, a, b = map(int, input().split()) map(int, input().split()) n b = map(int, input().split()) map(int, input().split()) b def binomial_coefficients_a(n, k):
    ans = 1
    for i in range(k):
        ans *= n-i
        ans *= modinv_table_a[i + 1]
        ans %= mod
    return ans def binomial_coefficients_a(n, k):
    ans = 1
    for i in range(k):
        ans *= n-i
        ans *= modinv_table_a[i + 1]
        ans %= mod
    return ans binomial_coefficients_a modinv_table_a = [-1] * (a+1) [-1] * (a+1) modinv_table_a
n, a, b = map(int, input().split())
mod = 10**9 + 7

modinv_table_a = [-1] * (a+1)
modinv_table_a[1] = 1
for i in range(2, a+1):
    modinv_table_a[i] = (-modinv_table_a[mod % i] * (mod // i)) % mod

modinv_table_b = [-1] * (b+1)
modinv_table_b[1] = 1
for i in range(2, b+1):
    modinv_table_b[i] = (-modinv_table_b[mod % i] * (mod // i)) % mod

def binomial_coefficients_a(n, k):
    ans = 1
    for i in range(k):
        ans *= n-i
        ans *= modinv_table_a[i + 1]
        ans %= mod
    return ans

def binomial_coefficients_b(n, k):
    ans = 1
    for i in range(k):
        ans *= n-i
        ans *= modinv_table_b[i + 1]
        ans %= mod
    return ans

res = (pow(2,n,mod)-binomial_coefficients_a(n,a)-binomial_coefficients_b(n,b)-1)%mod
print(res if res >= 0 else res+mod)