#include <iostream>

using namespace std;
using ll = long long;

const ll MOD = 1000000007;

template <typename T, typename U>
T mpow(T b, U n) {
    T ret = 1;
    while (n > 0) {
        if (n & 1) ret = ret * b % MOD;
        n >>= 1;
        b = b * b % MOD;
    }
    return ret;
}

const ll MAX_V = 100010;
ll fact[MAX_V + 1], invfact[MAX_V + 1];

void precalc() {
    invfact[0] = fact[0] = 1;
    for (ll i = 1; i <= MAX_V; ++i) {
        fact[i] = fact[i - 1] * i % MOD;
    }

    invfact[MAX_V] = mpow(fact[MAX_V], MOD - 2);
    for (ll i = MAX_V - 1; i >= 0; --i) {
        invfact[i] = invfact[i + 1] * (i + 1) % MOD;
    }
    return;
}

ll comb(ll a, ll b) {
    if (a < b) return 0;
    if (a == 0) return 1;  // a = b = 0
    return fact[a] * invfact[a - b] % MOD * invfact[b] % MOD;
}

int main() {
    precalc();
    int N;
    cin >> N;
    ll ans = 0;
    for (ll i = 0; i < N; ++i) {
        ll a;
        cin >> a;
        ans += a * comb(N - 1, i) % MOD;
    }
    cout << ans % MOD << endl;
    return 0;
}