#include <iostream>
#include <fstream>
#include <climits>
using namespace std;

ifstream f("podm.in");
ofstream g("podm.out");

long long n;
long long dp[505][505], a[505];
pair<long long,long long>mat[505];

void solve()
{
    long long st, dr;
    long long mini;
    for (long long k=1; k<n; ++k)
    {
        for (long long i=1; i+k<=n; ++i)
        {
            st=i;
            dr=i+k;
            mini=LLONG_MAX;
            for (long long t=st; t<dr; ++t)
            {
               mini=min(mini,dp[st][t]+dp[t+1][dr]+a[st]*a[t+1]*a[dr+1]);
            }
            dp[st][dr]=mini;
        }
    }
    g << dp[1][n];
}

int main()
{
    f >> n;
    f >> mat[1].first >> mat[1].second;
    a[1]=mat[1].first;
    a[2]=mat[1].second;
    for(long long i=2; i<=n; ++i)
    {
        mat[i].first=mat[i-1].second;
        f >> mat[i].second;
        a[i+1]=mat[i].second;
    }
    solve();
    return 0;
}