n,a,b = list(map(int, input().split()))
mod = int(1e9+7)

def inverse(n, mod):
    return pow(n, mod - 2, mod)

def cmb(n, r, mod):
    p, q = 1, 1
    for i in range(r):
        p = p * (n - i) % mod
        q = q * (i + 1) % mod
    return p * inverse(q, mod) % mod

ans = pow(2, n, mod) - 1
ans -= cmb(n, a, mod)
ans -= cmb(n, b, mod)
print(ans % mod) n,a,b = list(map(int, input().split())) n list(map(int, input().split())) list map(int, input().split()) map int input().split() ().split () input split a b mod = int(1e9+7) mod int(1e9+7) int 1e9+7 1e9 7 def inverse(n, mod):
    return pow(n, mod - 2, mod) inverse return pow(n, mod - 2, mod) pow(n, mod - 2, mod) pow n mod - 2 mod 2 mod n n mod mod def cmb(n, r, mod):
    p, q = 1, 1
    for i in range(r):
        p = p * (n - i) % mod
        q = q * (i + 1) % mod
    return p * inverse(q, mod) % mod cmb p, q = 1, 1 p 1 q 1 for i in range(r):
        p = p * (n - i) % mod
        q = q * (i + 1) % mod
     i range(r) range r p = p * (n - i) % mod p p * (n - i) % mod p * (n - i) p n - i n i mod q = q * (i + 1) % mod q q * (i + 1) % mod q * (i + 1) q i + 1 i 1 mod return p * inverse(q, mod) % mod p * inverse(q, mod) % mod p * inverse(q, mod) p inverse(q, mod) inverse q mod mod 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 -= cmb(n, a, mod) ans cmb(n, a, mod) cmb n a mod ans -= cmb(n, b, mod) ans cmb(n, b, mod) cmb n b mod print(ans % mod) print ans % mod ans mod ans -= cmb(n, a, mod) cmb(n, a, mod) ans mod = int(1e9+7) int(1e9+7) mod ans = pow(2, n, mod) - 1 pow(2, n, mod) - 1 ans def inverse(n, mod):
    return pow(n, mod - 2, mod) def inverse(n, mod):
    return pow(n, mod - 2, mod) inverse b = list(map(int, input().split())) list(map(int, input().split())) b n,a,b = list(map(int, input().split())) list(map(int, input().split())) n def cmb(n, r, mod):
    p, q = 1, 1
    for i in range(r):
        p = p * (n - i) % mod
        q = q * (i + 1) % mod
    return p * inverse(q, mod) % mod def cmb(n, r, mod):
    p, q = 1, 1
    for i in range(r):
        p = p * (n - i) % mod
        q = q * (i + 1) % mod
    return p * inverse(q, mod) % mod cmb ans -= cmb(n, b, mod) cmb(n, b, mod) ans a,b = list(map(int, input().split())) list(map(int, input().split())) a
n,a,b = list(map(int, input().split()))
mod = int(1e9+7)

def inverse(n, mod):
    return pow(n, mod - 2, mod)

def cmb(n, r, mod):
    p, q = 1, 1
    for i in range(r):
        p = p * (n - i) % mod
        q = q * (i + 1) % mod
    return p * inverse(q, mod) % mod

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