#include <bits/stdc++.h>
#define ll long long
#define INF 1000000000000000
#define MAXN 501

using namespace std;

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

ll d[MAXN][MAXN], v[MAXN];

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

    if(n == 1)
        fout << 0;
    else {
        for(int l = 2; l <= n; l++)
            for(int i = 1; i + l <= n + 1; i++) {
                int j = i + l;
                d[i][j] = INF;
                for(int k = i + 1; k < j; k++)
                    d[i][j] = min(d[i][j], d[i][k] + d[k][j] + v[i] * v[j] * v[k]);
            }

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