#include <bits/stdc++.h>

 using namespace std;

 typedef long long LL;

 const LL INF = 100000000000000000LL;

 LL num[];

 LL dp[][];

 int main() {

     LL ans = ;

     int n; cin >> n;

     for(int i = ; i <= n; i++) scanf("%lld", &num[i]), dp[i][i] = num[i];

     for(int len = ; len <= n; len++) {

         for(int l = ; l + len <= n; l++) {

             int r = l + len;

             dp[l][r] = INF;

             for(int k = l + ; k < r; k++) {

                 dp[l][r] = min(dp[l][r], dp[l][k] + dp[k][r] + num[l] * num[k] * num[r]);

             }

         }

     }

     cout << dp[][n] << endl;

     return ;

 }