N, A, B = [int(_) for _ in input().split()]
mod = 10**9 + 7
c = [1, N]
for i in range(1, B + 1):
    c += [c[-1] * (N - i) * pow(i + 1, mod - 2, mod) % mod]
ans = pow(2, N, mod) - c[A] - c[B] - 1
ans %= mod
print(ans) int(_) for _ in input().split() for _ in input().split() _ input().split() ().split () input split for _ in input().split() int(_) int _ N, A, B = [int(_) for _ in input().split()] N [int(_) for _ in input().split()] A B mod = 10**9 + 7 mod 10**9 + 7 10**9 10 9 7 c = [1, N] c [1, N] 1 N for i in range(1, B + 1):
    c += [c[-1] * (N - i) * pow(i + 1, mod - 2, mod) % mod] i range(1, B + 1) range 1 B + 1 B 1 c += [c[-1] * (N - i) * pow(i + 1, mod - 2, mod) % mod] c [c[-1] * (N - i) * pow(i + 1, mod - 2, mod) % mod] c[-1] * (N - i) * pow(i + 1, mod - 2, mod) % mod c[-1] * (N - i) * pow(i + 1, mod - 2, mod) c[-1] * (N - i) c[-1] c -1 N - i N i pow(i + 1, mod - 2, mod) pow i + 1 i 1 mod - 2 mod 2 mod mod ans = pow(2, N, mod) - c[A] - c[B] - 1 ans pow(2, N, mod) - c[A] - c[B] - 1 pow(2, N, mod) - c[A] - c[B] pow(2, N, mod) - c[A] pow(2, N, mod) pow 2 N mod c[A] c A c[B] c B 1 ans %= mod ans mod print(ans) print ans ans = pow(2, N, mod) - c[A] - c[B] - 1 pow(2, N, mod) - c[A] - c[B] - 1 ans mod = 10**9 + 7 10**9 + 7 mod B = [int(_) for _ in input().split()] [int(_) for _ in input().split()] B N, A, B = [int(_) for _ in input().split()] [int(_) for _ in input().split()] N A, B = [int(_) for _ in input().split()] [int(_) for _ in input().split()] A ans %= mod mod ans c += [c[-1] * (N - i) * pow(i + 1, mod - 2, mod) % mod] [c[-1] * (N - i) * pow(i + 1, mod - 2, mod) % mod] c c = [1, N] [1, N] c
N, A, B = [int(_) for _ in input().split()]
mod = 10**9 + 7
c = [1, N]
for i in range(1, B + 1):
    c += [c[-1] * (N - i) * pow(i + 1, mod - 2, mod) % mod]
ans = pow(2, N, mod) - c[A] - c[B] - 1
ans %= mod
print(ans)
