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

ans = pow(2, n, mod)-1

def choose(n, r):
    res = 1
    fac = 1
    for i in range(r):
        res *= n-i
        res %= mod
        fac *= i+1
        fac %= mod
    return res*pow(fac, mod-2, mod)%mod

ans -= choose(n, a)
ans -= choose(n, b)

print(ans%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 ans = pow(2, n, mod)-1 ans pow(2, n, mod)-1 pow(2, n, mod) pow 2 n mod 1 def choose(n, r):
    res = 1
    fac = 1
    for i in range(r):
        res *= n-i
        res %= mod
        fac *= i+1
        fac %= mod
    return res*pow(fac, mod-2, mod)%mod choose res = 1 res 1 fac = 1 fac 1 for i in range(r):
        res *= n-i
        res %= mod
        fac *= i+1
        fac %= mod
     i range(r) range r res *= n-i res n-i n i res %= mod res mod fac *= i+1 fac i+1 i 1 fac %= mod fac mod return res*pow(fac, mod-2, mod)%mod res*pow(fac, mod-2, mod)%mod res*pow(fac, mod-2, mod) res pow(fac, mod-2, mod) pow fac mod-2 mod 2 mod mod n n r r ans -= choose(n, a) ans choose(n, a) choose n a ans -= choose(n, b) ans choose(n, b) choose n b print(ans%mod) print ans%mod ans mod n, a, b = map(int, input().split()) map(int, input().split()) n ans -= choose(n, a) choose(n, a) ans ans -= choose(n, b) choose(n, b) ans ans = pow(2, n, mod)-1 pow(2, n, mod)-1 ans b = map(int, input().split()) map(int, input().split()) b mod = 10**9+7 10**9+7 mod a, b = map(int, input().split()) map(int, input().split()) a def choose(n, r):
    res = 1
    fac = 1
    for i in range(r):
        res *= n-i
        res %= mod
        fac *= i+1
        fac %= mod
    return res*pow(fac, mod-2, mod)%mod def choose(n, r):
    res = 1
    fac = 1
    for i in range(r):
        res *= n-i
        res %= mod
        fac *= i+1
        fac %= mod
    return res*pow(fac, mod-2, mod)%mod choose
n, a, b = map(int, input().split())
mod = 10**9+7

ans = pow(2, n, mod)-1

def choose(n, r):
    res = 1
    fac = 1
    for i in range(r):
        res *= n-i
        res %= mod
        fac *= i+1
        fac %= mod
    return res*pow(fac, mod-2, mod)%mod

ans -= choose(n, a)
ans -= choose(n, b)

print(ans%mod)