#include <fstream>
using namespace std;

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

int n, i, j, k, l;
long long dp[505][505], v[505];

int main(void) {
    in >> n; n++;
    for( i = 1; i <= n; i ++ ){
        in >> v[i];
    }
    for( l = 3; l <= n; l ++ ){
        for( i = 1, j = l; j <= n; i ++, j ++ ) {
            dp[i][j] = numeric_limits<long long> :: max() / 2;
            for( k = i+1; k <= j-1; k ++ ){
                dp[i][j] = min( dp[i][j], dp[i][k]+dp[k][j] + v[i]*v[j]*v[k] );
            }
        }
    }
    
    out << dp[1][n];
    return 0;
}