#ifndef LOCAL
#include <bits/stdc++.h>

using namespace std;

#define debug(...) (void(0))
#else
#include "algo/debug.h"
#endif

#include <atcoder/modint>
using mint = atcoder::modint1000000007;

void solve() {
    int N; cin >> N;
    vector<mint> A(N);
    for(int i = 0; i < N; i++) {
        int a; cin >> a;
        A[i] = a;
    }
    int iter = N - 1;
    for(;iter--;) {
        for(int i = 0; i + 1 < N; i++) {
            A[i] = A[i] + A[i + 1];
        }
    }
    cout << A.begin()->val() << endl;
}

int main() {
    std::ios::sync_with_stdio(false);
    std::cin.tie(nullptr);
    int tt = 1;
    // std::cin >> tt;
    while (tt--) {
        solve();
    }
}