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

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

	T combi(int n, int r) {
		if (n < 0 || n < r || r < 0) return 0;
		return fct[n] * (finv[r] * finv[n - r] % mod) % 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;
}