n, a, b = list(map(int, input().split()))

MOD = 10**9+7





def COM(n, r):

    X = Y = 1

    if n-r < r:

        r = n-r

    for i in range(1, r+1):

        Y = Y*i % MOD

        X = X*(n-i+1) % MOD

    Y = pow(Y, MOD-2, MOD)

    return X*Y



ans = pow(2, n, MOD)-1 - COM(n, a)-COM(n, b)

ans %= MOD



print(ans)

n, a, b = list(map(int, input().split()))

MOD = 10**9+7

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

X = Y = 1

for i in range(1, b+1):

    Y = Y*i % MOD

    X = X*(n-i+1) % MOD

    if i == a or i == b:

        ans -= X*pow(Y, MOD-2, MOD)



print((ans % MOD))
n, a, b = list(map(int, input().split()))
MOD = 10**9 + 7


def COM(n, r):
    X = Y = 1
    if n - r < r:
        r = n - r
    for i in range(1, r + 1):
        Y = Y * i % MOD
        X = X * (n - i + 1) % MOD
    Y = pow(Y, MOD - 2, MOD)
    return X * Y


ans = pow(2, n, MOD) - 1 - COM(n, a) - COM(n, b)
ans %= MOD
print(ans)

n, a, b = list(map(int, input().split()))
MOD = 10**9 + 7
ans = pow(2, n, MOD) - 1
X = Y = 1
for i in range(1, b + 1):
    Y = Y * i % MOD
    X = X * (n - i + 1) % MOD
    if i == a or i == b:
        ans -= X * pow(Y, MOD - 2, MOD)
print((ans % MOD))

- - -def COM(n, r): -    X = Y = 1 -    if n - r < r: -        r = n - r -    for i in range(1, r + 1): -        Y = Y * i % MOD -        X = X * (n - i + 1) % MOD -    Y = pow(Y, MOD - 2, MOD) -    return X * Y - - -ans = pow(2, n, MOD) - 1 - COM(n, a) - COM(n, b) -ans %= MOD -print(ans) +ans = pow(2, n, MOD) - 1 +X = Y = 1 +for i in range(1, b + 1): +    Y = Y * i % MOD +    X = X * (n - i + 1) % MOD +    if i == a or i == b: +        ans -= X * pow(Y, MOD - 2, MOD) +print((ans % MOD))