#include <fstream>
#define f in
#define g out
#define INF 10000000000000LL;

using namespace std;
ifstream in ( "podm.in" );
ofstream out( "podm.out" );
long long i, j, n, k, l;
long long v[510], d[510][510];

int main() {
    f>>n; n++;
    for ( i=1; i <= n; i++ )
        f>>v[i];
    
    for ( l = 3; l <= n; l++ )
        for ( i=1; i+l-1 <= n; i++ ){
            j = i+l-1;
            d[i][j] = INF;
            for ( k = i+1; k < j; k++ )
                d[i][j] = min ( d[i][j], d[i][k]+d[k][j]+v[i]*v[k]*v[j] );
        }
    g<<d[1][n];
    return 0;
}