#include<fstream>
using namespace std;
int n, i, j, k, ii;
long long v[505], d[505][505];
ifstream fin("podm.in");
ofstream fout("podm.out");
int main(){
    fin>> n;
    n++;
    for(i = 1; i <= n; i++){
        fin>> v[i];
    }
    for(ii = 2; ii <= n; ii++){
        for(i = 1; i + ii <= n; i++){
            j = i + ii;
            d[i][j] = 1000000000000LL;
            for(k = i + 1; k < j; k++){
                d[i][j] = min(d[i][j], d[i][k] + d[k][j] + v[i] * v[j] * v[k]);
            }
        }
    }
    fout<< d[1][n] <<"\n";
    return 0;
}