n, a, b = map(int, input().split())
# 全通り - nCa - nCb
mod = 10 ** 9 + 7


def inv(x):
    return pow(x, mod - 2, mod)

# n ~ n - k + 1


def c(n, k):
    res = 1
    for i in range(0, k):
        res = res * (n - i) * inv(i + 1) % mod
    return res


print(((pow(2, n, mod) - c(n, a) - c(n, b) - 1) % mod + mod) % 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 def inv(x):
    return pow(x, mod - 2, mod)

# n ~ n - k + 1 inv return pow(x, mod - 2, mod) pow(x, mod - 2, mod) pow x mod - 2 mod 2 mod x x def c(n, k):
    res = 1
    for i in range(0, k):
        res = res * (n - i) * inv(i + 1) % mod
    return res c res = 1 res 1 for i in range(0, k):
        res = res * (n - i) * inv(i + 1) % mod
     i range(0, k) range 0 k res = res * (n - i) * inv(i + 1) % mod res res * (n - i) * inv(i + 1) % mod res * (n - i) * inv(i + 1) res * (n - i) res n - i n i inv(i + 1) inv i + 1 i 1 mod return res res n n k k print(((pow(2, n, mod) - c(n, a) - c(n, b) - 1) % mod + mod) % mod) print ((pow(2, n, mod) - c(n, a) - c(n, b) - 1) % mod + mod) % mod (pow(2, n, mod) - c(n, a) - c(n, b) - 1) % mod + mod (pow(2, n, mod) - c(n, a) - c(n, b) - 1) % mod pow(2, n, mod) - c(n, a) - c(n, b) - 1 pow(2, n, mod) - c(n, a) - c(n, b) pow(2, n, mod) - c(n, a) pow(2, n, mod) pow 2 n mod c(n, a) c n a c(n, b) c n b 1 mod mod mod n, a, b = map(int, input().split()) map(int, input().split()) n a, b = map(int, input().split()) map(int, input().split()) a def inv(x):
    return pow(x, mod - 2, mod)

# n ~ n - k + 1 def inv(x):
    return pow(x, mod - 2, mod)

# n ~ n - k + 1 inv mod = 10 ** 9 + 7 10 ** 9 + 7 mod def c(n, k):
    res = 1
    for i in range(0, k):
        res = res * (n - i) * inv(i + 1) % mod
    return res def c(n, k):
    res = 1
    for i in range(0, k):
        res = res * (n - i) * inv(i + 1) % mod
    return res c b = map(int, input().split()) map(int, input().split()) b
n, a, b = map(int, input().split())
# 全通り - nCa - nCb
mod = 10 ** 9 + 7


def inv(x):
    return pow(x, mod - 2, mod)

# n ~ n - k + 1


def c(n, k):
    res = 1
    for i in range(0, k):
        res = res * (n - i) * inv(i + 1) % mod
    return res


print(((pow(2, n, mod) - c(n, a) - c(n, b) - 1) % mod + mod) % mod)
