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

def modcmb(n,r,mod):
    x,y = 1,1
    for i in range(1, r + 1):
        x *= (n - i + 1)
        x %= mod
        y *= i
        y %= mod
    rtn = x * pow(y, mod - 2, mod) % mod
    return rtn

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

def modcmb(n,r,mod):
    x,y = 1,1
    for i in range(1, r + 1):
        x *= (n - i + 1)
        x %= mod
        y *= i
        y %= mod
    rtn = x * pow(y, mod - 2, mod) % mod
    return rtn

ans = pow(2, n, mod) - 1
ans -= modcmb(n,a,mod) + modcmb(n,b,mod)
print(ans % mod)
