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

#ifndef SPX
ifstream fin("podm.in");
ofstream fout("podm.out");
#define cin fin
#define cout fout
#endif

const int N = 502;

int n;
long d[N];
long dp[N][N];

int main() {
  cin >> n;
  for (int i = 0; i <= n; ++i) {
    cin >> d[i];
  }
  for (int len = 2; len <= n; ++len) {
    for (int i = 0; i <= n - len; ++i) {
      dp[i][i + len - 1] =
          min(d[i] * d[i + 1] * d[i + len] + dp[i + 1][i + len - 1],
              d[i] * d[i + len - 1] * d[i + len] + dp[i][i + len - 2]);
    }
  }
  cout << dp[0][n - 1] << endl;
}