#include <atcoder/all>
#include <bits/stdc++.h>
#define rep(i, a, b) for (ll i = (ll)(a); i < (ll)(b); i++)
using namespace atcoder;
using namespace std;

typedef long long ll;

int main() {
    int n;
    cin >> n;
    assert(n <= 100);
    vector<int> a(n);
    rep(i, 0, n) cin >> a[i];
    ll ans = 0;
    rep(i, 0, n) rep(j, 0, n) { ans += abs(i - j) * abs(a[i] - a[j]); }
    cout << ans << endl;
}