#include <fstream>
#define inf 1000000000000000

using namespace std;

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

long long n, v[502], i, j, d[502][502], k, len;

int main(){
    fin>>n;
    for(i=1;i<=n+1;i++)
        fin>>v[i];
    for(i=1;i<=n+1;i++)
        for(j=i+1;j<=n+1;j++)
            d[i][j] = inf;
    for(i=1;i<=n;i++)
        d[i][i+1] = 0;

    for(len = 2;len <= n;len++)
        for(i=1;i+len <= n+1;i++)       /// intervalul este i ... i+len
            for(k=i+1;k<=i+len-1;k++)
                d[i][i+len] = min(d[i][i+len], d[i][k] + d[k][i+len] + v[i]*v[k]*v[i+len]);


    fout<<d[1][n+1];
    return 0;
}