#include <iostream>
#include <cstdio>
#include <algorithm>
#include <set>
#include <map>
#include <stack>
#include <cmath>
#include <queue>
#include <deque>
#include <cassert>
#include <string>
#include <iomanip>
using namespace std;

#define INF 1000000000
#define lint long long
#define mp make_pair
#define pb push_back
#define MOD 1000000007

int a[100005];
int main()
{
    int n;
    scanf("%d", &n);

    for (int i = 1; i <= n; ++i)
    {
        scanf("%d", &a[i]);
    }

    int ans = a[1];
    int sumOfProducts = a[1];
    for (int i = 2; i <= n; ++i)
    {
        ans = (ans + ans*1ll*a[i] + a[i] + sumOfProducts * 1ll * a[i]) % MOD;
        sumOfProducts = (sumOfProducts + sumOfProducts * 1ll * a[i] + a[i]) % MOD;
    }

    printf("%d", ans);
    return 0;
}