#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int INF = 1e9 + 10;
const ll INFL = 4e18;

int main() {
    ll N;
    cin >> N;
    vector<ll> A(N);
    for (int i = 0; i < N; i++) cin >> A[i];

    ll ans = 0;
    for (int i = 0; i < N; i++) {
        for (int j = 0; j < N; j++) {
            ans += abs(i - j) * abs(A[i] - A[j]);
        }
    }

    cout << ans << endl;
}