#include <algorithm>
#include <iostream>
#include <vector>
#define MOD 1000000007
using namespace std;

template<typename T>
struct combination {
	vector<T> fct, inv;
	T mod;

	T power(T m, T n, T mod) {
		if (n == 0) return 1;
		long res = power(m, n / 2, mod);
		if (n % 2) res = res * res % mod * m % mod;
		else res = res * res % mod;
		return res;
	}

	combination(int size, T newMod) {
		fct = vector<T>(size + 1, 1);
		inv = vector<T>(size + 1, 1);
		mod = newMod;
		for (int i = 1; i <= size; ++i) {
			fct[i] = fct[i - 1] * i % mod;
			inv[i] = power(fct[i], mod - 2, mod);
		}
	}

	T combi(int n, int r) {
		return fct[n] * inv[n - r] % mod * inv[r] % mod;
	}
};

int main() {
	int N;
	cin >> N;
	vector<long> a(N);
	for (long& i : a) cin >> i;
	long sum = 0;
	combination<long> cmb(N - 1, MOD);
	for (int i = 0; i < N; ++i) sum = a[i] * cmb.combi(N - 1, i) % MOD + sum % MOD;
	cout << sum % MOD;
}