class ModComb: def __init__(self, n: int, mod: int): fact = [0] * (n+1) fact[0] = 1 for i in range(1, n+1): fact[i] = i * fact[i-1] % mod ifact = [0] * (n+1) ifact[n] = pow(fact[n], mod-2, mod) for i in range(n, 0, -1): ifact[i-1] = ifact[i] * i % mod self.fact = fact self.ifact = ifact self.mod = mod def __call__(self, n: int, k: int) -> int: if n < 0 or k > n: return 0 return (self.fact[n] * self.ifact[k] % self.mod) * self.ifact[n-k] % self.mod MOD = 10**9 + 7 N = int(input()) A = list(map(int, input().split())) mcomb = ModComb(N, MOD) ans = 0 for i, a in enumerate(A): ans += mcomb(N-1, i) * a ans %= MOD print(ans)