#include <iostream>
#include <cmath>
using namespace std;

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

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

    cout << result << endl;
    return 0;
}