#include <fstream>
using namespace std;

long long dp[505][505];     size_t m[505], n;

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

    fin >> n;
    for(size_t i = 0; i <= n; i++) fin >> m[i];


    for(size_t l = 2; l <= n; ++l) for(size_t i = 1; i <= n - l + 1; ++i)
    {
        size_t j = i + l- 1;  dp[i][j] = 1000000000000000;

        for(size_t k = i; k < j; k++) dp[i][j] = min(dp[i][j], dp[i][k] + dp[k + 1][j] + m[i - 1] * m[k] * m[j] * 1LL);
    }
    fout << dp[1][n];
}