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

#ifdef LOCAL
#include <debug.hpp>
#else
#define debug(...)
#endif

int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);
    cout << fixed << setprecision(20);
    int N;
    cin >> N;
    vector<int> 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 << '\n';
}