#include <iostream>
#include <fstream>

using namespace std;

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

#define NMax 510
#define ll long long
long long inf = (1e18);

int n;
int d[NMax];
long long c[NMax][NMax];

void init();
ll rezolvare(int, int);

int main(){
	init();
	rezolvare(1, n);
	fout << c[1][n];
}

void init(){
	int i, j;
	fin >> n;
	for(i = 0; i <= n; i++)
		fin >> d[i];
	
	for(i = 1; i <= n; i++)
		for(j = 1; j <= n; j++)
			c[i][j] = inf;
}

ll rezolvare(int i, int j){
	ll p;
	if(c[i][j] < inf) return c[i][j];
	if(i == j)
		c[i][j] = 0;
	else
		for(int k = i; k < j; k++){
			p = rezolvare(i, k) + rezolvare(k + 1, j) + 1LL * d[i - 1] * d[k] * d[j];
			if(p < c[i][j]) c[i][j] = p;
		}
	return c[i][j];
}