#include<stdio.h>
#include<algorithm>
using namespace std;
#define NMAX 500
long long sz[NMAX+5],d[NMAX+5][NMAX+5];
const long long INF = 1e18;
int main() {
    freopen("podm.in","r",stdin);
    freopen("podm.out","w",stdout);
    int l,n,j,k,i;

    scanf("%d",&n);
    for(i = 1; i <= n + 1 ; i++)
        scanf("%lld",&sz[i]);

    for(i = 1; i < n ; i++)
        d[i][i + 1] = sz[i] * sz[i + 1] * sz[i + 2];

    for(l = 2; l < n; l++) {
        j = l+1;
        i = 1;
        while(i <= n && j <= n) {
            d[i][j] = INF;
            for(k = i; k < j ;k++)
                d[i][j] = min (d[i][j], d[i][k] + d[k+1][j] + sz[i] * sz[k + 1] * sz[j + 1]);
            i++;
            j++;
            }
        }
    printf("%lld\n",d[1][n]);
    return 0;
}