#include <fstream>
#define INF 1000000000000000LL

using namespace std;

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

int n,i,j,k,x[505],L;
long long D[505][505];

long long rec(int st, int dr) {
    if (D[st][dr] != INF)
        return D[st][dr];
    if (dr == st + 1) {
        D[st][dr] = 0;
        return 0;
    }

///    D[st][dr] = INF;
    for (int i=st+1;i<dr;i++)
        D[st][dr] = min(D[st][dr], rec(st, i) + rec(i, dr) + x[st]*(long long)x[i]*x[dr]);
    return D[st][dr];
}

int main()
{
    fin >> n;
    n++;
    for (i=1; i<=n; i++)
        fin >> x[i];

    for (i=1; i<=n-1; i++)
        for (j=i+1; j<=n; j++)
            D[i][j] = INF;

    fout << rec(1, n);
    return 0;
}