# AtCoder Beginner Contest 156
# D - Bouquet
# https://atcoder.jp/contests/abc156/tasks/abc156_d
n, a, b = map(int, input().split())
mod = 10**9 + 7

MAX = 202020

cmb = [0]*MAX
facinv = [0]*MAX
inv = [0]*MAX


def nCk_init(n, mod, MAX):
    facinv[0] = facinv[1] = 1
    inv[1] = 1
    for i in range(2, MAX):
        inv[i] = -inv[mod % i] * (mod // i) % mod
        facinv[i] = facinv[i-1] * inv[i] % mod
    cmb[0] = 1
    for i in range(1, MAX):
        cmb[i] = cmb[i-1] * ((n-i+1)*inv[i] % mod) % mod


nCk_init(n, mod, MAX)
ans = pow(2, n, mod)
ans += mod - cmb[a]
ans %= mod
ans += mod - cmb[b]
ans %= mod
ans += mod - 1
ans %= mod
print(ans) 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 MAX = 202020 MAX 202020 cmb = [0]*MAX cmb [0]*MAX [0] 0 MAX facinv = [0]*MAX facinv [0]*MAX [0] 0 MAX inv = [0]*MAX inv [0]*MAX [0] 0 MAX def nCk_init(n, mod, MAX):
    facinv[0] = facinv[1] = 1
    inv[1] = 1
    for i in range(2, MAX):
        inv[i] = -inv[mod % i] * (mod // i) % mod
        facinv[i] = facinv[i-1] * inv[i] % mod
    cmb[0] = 1
    for i in range(1, MAX):
        cmb[i] = cmb[i-1] * ((n-i+1)*inv[i] % mod) % mod nCk_init facinv[0] = facinv[1] = 1 facinv[0] facinv 0 1 = facinv[1] = 1 facinv[1] facinv 1 1 inv[1] = 1 inv[1] inv 1 1 for i in range(2, MAX):
        inv[i] = -inv[mod % i] * (mod // i) % mod
        facinv[i] = facinv[i-1] * inv[i] % mod
     i range(2, MAX) range 2 MAX inv[i] = -inv[mod % i] * (mod // i) % mod inv[i] inv i -inv[mod % i] * (mod // i) % mod -inv[mod % i] * (mod // i) -inv[mod % i] inv[mod % i] inv mod % i mod i mod // i mod i mod facinv[i] = facinv[i-1] * inv[i] % mod facinv[i] facinv i facinv[i-1] * inv[i] % mod facinv[i-1] * inv[i] facinv[i-1] facinv i-1 i 1 inv[i] inv i mod cmb[0] = 1 cmb[0] cmb 0 1 for i in range(1, MAX):
        cmb[i] = cmb[i-1] * ((n-i+1)*inv[i] % mod) % mod i range(1, MAX) range 1 MAX cmb[i] = cmb[i-1] * ((n-i+1)*inv[i] % mod) % mod cmb[i] cmb i cmb[i-1] * ((n-i+1)*inv[i] % mod) % mod cmb[i-1] * ((n-i+1)*inv[i] % mod) cmb[i-1] cmb i-1 i 1 (n-i+1)*inv[i] % mod (n-i+1)*inv[i] n-i+1 n-i n i 1 inv[i] inv i mod mod n n mod mod MAX MAX nCk_init(n, mod, MAX) nCk_init n mod MAX ans = pow(2, n, mod) ans pow(2, n, mod) pow 2 n mod ans += mod - cmb[a] ans mod - cmb[a] mod cmb[a] cmb a ans %= mod ans mod ans += mod - cmb[b] ans mod - cmb[b] mod cmb[b] cmb b ans %= mod ans mod ans += mod - 1 ans mod - 1 mod 1 ans %= mod ans mod print(ans) print ans MAX = 202020 202020 MAX ans = pow(2, n, mod) pow(2, n, mod) ans ans %= mod mod ans ans %= mod mod ans inv = [0]*MAX [0]*MAX inv ans += mod - 1 mod - 1 ans n, a, b = map(int, input().split()) map(int, input().split()) n ans += mod - cmb[a] mod - cmb[a] ans mod = 10**9 + 7 10**9 + 7 mod ans += mod - cmb[b] mod - cmb[b] ans def nCk_init(n, mod, MAX):
    facinv[0] = facinv[1] = 1
    inv[1] = 1
    for i in range(2, MAX):
        inv[i] = -inv[mod % i] * (mod // i) % mod
        facinv[i] = facinv[i-1] * inv[i] % mod
    cmb[0] = 1
    for i in range(1, MAX):
        cmb[i] = cmb[i-1] * ((n-i+1)*inv[i] % mod) % mod def nCk_init(n, mod, MAX):
    facinv[0] = facinv[1] = 1
    inv[1] = 1
    for i in range(2, MAX):
        inv[i] = -inv[mod % i] * (mod // i) % mod
        facinv[i] = facinv[i-1] * inv[i] % mod
    cmb[0] = 1
    for i in range(1, MAX):
        cmb[i] = cmb[i-1] * ((n-i+1)*inv[i] % mod) % mod nCk_init ans %= mod mod ans cmb = [0]*MAX [0]*MAX cmb a, b = map(int, input().split()) map(int, input().split()) a facinv = [0]*MAX [0]*MAX facinv b = map(int, input().split()) map(int, input().split()) b
# AtCoder Beginner Contest 156
# D - Bouquet
# https://atcoder.jp/contests/abc156/tasks/abc156_d
n, a, b = map(int, input().split())
mod = 10**9 + 7

MAX = 202020

cmb = [0]*MAX
facinv = [0]*MAX
inv = [0]*MAX


def nCk_init(n, mod, MAX):
    facinv[0] = facinv[1] = 1
    inv[1] = 1
    for i in range(2, MAX):
        inv[i] = -inv[mod % i] * (mod // i) % mod
        facinv[i] = facinv[i-1] * inv[i] % mod
    cmb[0] = 1
    for i in range(1, MAX):
        cmb[i] = cmb[i-1] * ((n-i+1)*inv[i] % mod) % mod


nCk_init(n, mod, MAX)
ans = pow(2, n, mod)
ans += mod - cmb[a]
ans %= mod
ans += mod - cmb[b]
ans %= mod
ans += mod - 1
ans %= mod
print(ans)
