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

MOD = 10**9+7



def cmb(n,r):

    a,b = 1,1

    for i in range(r):

        a = a * (n-i) % MOD

        b = b * (i+1) % MOD

    return a * pow(b, MOD-2, MOD)%MOD



print(((pow(2,n,MOD) - cmb(n,a) - cmb(n,b) - 1)%MOD))
n,a,b = list(map(int, input().split()))

mod = 10**9+7



def cmb(n,r):

    a,b = 1,1

    for i in range(r):

        a = a * (n-i) % mod

        b = b * (i+1) % mod

    return a * pow(b, mod-2, mod) %mod



print(((pow(2, n, mod) - cmb(n,a) - cmb(n,b) - 1)%mod))
n, a, b = list(map(int, input().split()))
MOD = 10**9 + 7


def cmb(n, r):
    a, b = 1, 1
    for i in range(r):
        a = a * (n - i) % MOD
        b = b * (i + 1) % MOD
    return a * pow(b, MOD - 2, MOD) % MOD


print(((pow(2, n, MOD) - cmb(n, a) - cmb(n, b) - 1) % MOD))

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


def cmb(n, r):
    a, b = 1, 1
    for i in range(r):
        a = a * (n - i) % mod
        b = b * (i + 1) % mod
    return a * pow(b, mod - 2, mod) % mod


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

-MOD = 10**9 + 7 +mod = 10**9 + 7 -        a = a * (n - i) % MOD -        b = b * (i + 1) % MOD -    return a * pow(b, MOD - 2, MOD) % MOD +        a = a * (n - i) % mod +        b = b * (i + 1) % mod +    return a * pow(b, mod - 2, mod) % mod -print(((pow(2, n, MOD) - cmb(n, a) - cmb(n, b) - 1) % MOD)) +print(((pow(2, n, mod) - cmb(n, a) - cmb(n, b) - 1) % mod))