#include <iostream>
#include <string>
#include <utility>
#include <algorithm>
#include <map>
#include <set>
#include <vector>
#include <cmath>
#include <cstdlib>
#include <queue>
#include <stack>
#include <iomanip>


using namespace std;

#define REP(i, n) for(ll i = 0;i < n;i++)
#define REPR(i, n) for(ll i = n;i >= 0;i--)
#define FOR(i, m, n) for(ll i = m;i < n;i++)
#define FORR(i, m, n) for(ll i = m;i >= n;i--)
#define REPO(i, n) for(ll i = 1;i <= n;i++)
#define ll long long
#define INF 1999999999
#define MINF -1999999999
#define INF64 1999999999999999999
#define ALL(n) n.begin(),n.end()
#define MOD 1000000007


ll n, ans = 0, f[110000];

ll kn(ll a, ll b) {
	a %= MOD;
	ll res = 1;
	while (b > 0) {
		if (b % 2 == 1)res *= a;
		b /= 2;
		a *= a;
		a %= MOD;
		res %= MOD;
	}
	return res;
}

ll com(ll a, ll b) {
	return f[a] * kn(f[a - b] * f[b], MOD - 2) % MOD;
}

int main() {
	cin >> n;
	f[1] = 1;
	f[0] = 1;
	REPO(i, 100000)f[i + 1] = f[i] * (i + 1) % MOD;
	REP(i, n) {
		ll a;
		cin >> a;
		ans += a * com(n - 1, i);
		ans %= MOD;
	}
	cout << ans << endl;
}