#include <iostream>
using namespace std;

int main()
{
    int N, i;
    cin >> N;
    int N2 = N / 2;
    int a[100001];
    int b[100001];
    int ans = 0;
    b[0] = 1;
    for (i = 1; i < N2+1; ++i) {
        b[i] = b[i-1]*(N-i)/i;
    }
    for (i = 0; i < N; ++i) {
        cin >> a[i];
    }
    for (i = 0; i < N2; ++i) {
        ans += (a[i]+a[N-1-i])*b[i];
        ans %= 1000000007;
    }
    if (N%2 == 1) {
        ans += a[N2]*b[N2];
    }
    cout << ans % 1000000007 << endl;
}