#include <vector>
#include <fstream>
#include <cstdlib>
#include <iterator>
#include <algorithm>
#define N_MAX 511
#define oo 99999999999999999LL

using namespace std;
long long int R[N_MAX][N_MAX];
vector< int > d;
int main( void )
{
    int N, i, j, k;
    ifstream in( "podm.in" );
    in>>N;
    copy( istream_iterator<int>(in), istream_iterator<int>(), back_inserter(d) );
    for( i=N-1; i; --i )
    {
        R[i][i+1]=1LL*d[i-1]*d[i]*d[i+1];
        for( j=i+2; j <= N; ++j )
        {
            R[i][j]=oo;
            for( k=1; k < j; ++k )
                R[i][j]=min( R[i][j], R[i][k]+R[k+1][j]+1LL*d[i-1]*d[k]*d[j] );
        }
    }
    ofstream out( "podm.out" );
    out<<R[1][N]<<'\n';
    return EXIT_SUCCESS;
}