#include <iostream>
#include <fstream>
#include <bits/stdc++.h>
#define VMAX 505
using namespace std;

ifstream fin ("podm.in");
ofstream fout ("podm.out");

int dp[VMAX][VMAX];
int numere[VMAX];
struct matrix{
int lin,col;
};
matrix nrr[VMAX];
int main()
{
    ios_base::sync_with_stdio(0);
    int n,m,i,j,k,t,q,nr,maxim,minim,suma;
    fin>>n;
    for(i=0;i<=n;i++)
        fin>>numere[i];
    for(i=0;i<=n;i++)
    {
        nrr[i].lin=numere[i];
        nrr[i].col=numere[i+1];
    }
    for(i=0;i<=n;i++)
        for(j=0;j<=n;j++)
            dp[i][j]=2000000000;

    for(i=n-1;i>=0;i--)
    {
        dp[i][i]=0;
        dp[i][i+1]=nrr[i].lin * nrr[i].col * nrr[i+1].col;
        for(j=i+2;j<n;j++)
        {
            for(k=i;k<j;k++)
            {
                dp[i][j]=min(dp[i][k]+dp[k+1][j]+nrr[i].lin*nrr[k].col*nrr[j].col,dp[i][j]);
            }
        }
    }
    fout<<dp[0][n-1]<<'\n';



    return 0;
}