#include <algorithm>
#include <cassert>
#include <cctype>
#include <chrono>
#define _USE_MATH_DEFINES
#include <cmath>
#include <cstdio>
#include <cstring>
#include <ctime>
#include <deque>
#include <functional>
#include <iostream>
#include <map>
#include <queue>
#include <random>
#include <set>
#include <sstream>
#include <string>
#include <tuple>
#include <vector>
using namespace std;

#define FOR(i,m,n) for(int i=(m);i<(n);++i)
#define REP(i,n) FOR(i,0,n)
#define ALL(v) (v).begin(),(v).end()

const int INF = 0x3f3f3f3f, MOD = 1000000007;
const long long LINF = 0x3f3f3f3f3f3f3f3fLL;
/*-----------------------------------------*/
vector<long long> inv_init(int num) {
  vector<long long> inv(num + 1, 0);
  inv[1] = 1;
  FOR(i, 2, num + 1) inv[i] = MOD - inv[MOD % i] * (MOD / i) % MOD;
  return inv;
}

vector<long long> nCk_init(long long n, int k) {
  vector<long long> k_inv = inv_init(k), nCk(k + 1);
  nCk[0] = 1;
  int high = min(n, (long long)k) + 1;
  FOR(i, 1, high) {
    nCk[i] = nCk[i - 1] * n % MOD * k_inv[i] % MOD;
    --n;
  }
  FOR(i, high, k + 1) nCk[i] = 0;
  return nCk;
}

int main() {
  cin.tie(0); ios::sync_with_stdio(false);
  // freopen("input.txt", "r", stdin);

  int n; cin >> n;
  long long ans = 0;
  vector<long long> nCk = nCk_init(n - 1, n - 1);
  REP(i, n) {
    int a; cin >> a;
    (ans += a * nCk[i] % MOD) %= MOD;
  }
  cout << ans << '\n';
  return 0;
}