// Include
#include <fstream>
using namespace std;

// Definitii
#define ll long long

// Constante
const int sz = 501;
const ll oo = (1LL<<62)-1;

// Functii
ll sum(int left, int right);

// Variabile
ifstream in("podm.in");
ofstream out("podm.out");

int num;
int sizes[sz];
ll memoize[sz][sz];

// Main
int main()
{
	in >> num;
	
	for(int i=0 ; i<=num ; ++i)
		in >> sizes[i];
	
	out << sum(1, num);
	
	in.close();
	out.close();
	return 0;
}

ll sum(int left, int right)
{
	if(left == right)
		return 0;
	
	if(memoize[left][right])
		return memoize[left][right];
	
	if(right - left == 1)
		return memoize[left][right] = 1LL*sizes[left-1] * 1LL*sizes[left] * 1LL*sizes[right];
	
	ll minVal = oo;
	
	for(int mid=left ; mid<right ; ++mid)
		minVal = min(minVal, 1LL*sizes[left-1] * 1LL*sizes[mid] * 1LL*sizes[right] + 1LL*sum(left, mid) + 1LL*sum(mid+1, right));
	
	return memoize[left][right] = minVal;
}