#include <bits/stdc++.h>
using namespace std;
using ll = long long;

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);

    const int mod = 1000000007;
    int N;
    cin >> N;

    assert(1 <= N && N <= 100000);

    ll s = 0, s1 = 0;
    vector<ll> x(N);
    for(auto &v : x){
        cin >> v;
        assert(1 <= v && v <= 1000000000);

        s += v;
        s1 += v * v;
    }

    assert(1 <= s && s <= 1000000000);

    auto inv = [&](ll v){
        ll res = 1, d = v % mod;
        for(int i = 0; i < 30; i++){
            if(1000000005 >> i & 1)(res *= d) %= mod; 
            (d *= d) %= mod;
        }
        return res;
    };

    cout << (1 + (s * s - s1) % mod * inv(s)) % mod << '\n';
}