#include<cstdio>
#include<algorithm>
#define inf ~(1LL<<63)
using namespace std;

const int NMAX=505;
int D[NMAX];
long long C[NMAX][NMAX];

int main(){
    freopen("podm.in","r",stdin);
    freopen("podm.out","w",stdout);
    int n;
    scanf("%d", &n);
    for(int i=1;i<=n+1;i++)
        scanf("%d", &D[i]);
    for(int i=1;i<=n;i++){
        for(int j=1;j<=n;j++)
            C[i][j]=inf;
        C[i][i]=0;
    }
    for(int k=2;k<=n;k++)
        for(int i=1;i<=n-k+1;i++)
            for(int j=i;j<i+k-1;j++)
                C[i][i+k-1]=min(C[i][i+k-1], C[i][j]+C[j+1][i+k-1]+D[i]*D[j+1]*D[i+k]);
    printf("%lld", C[1][n]);
    return 0;
}