#include<fstream>
using namespace std;

ifstream f("podm.in");
ofstream g("podm.out");

long long d[1<<9];
long long bst[1<<9][1<<9],aux;
long long Inf = 1LL << 60;
int i,j,k,N;

int main () {
	f>>N;
	for ( i = 1 ; i <= N + 1 ; ++i ){
		f>>d[i];
	}
	for ( i = 2 ; i <= N ; ++i ){
		bst[i][i+1]  = 1LL * d[i-1] * d[i] * d[i+1];
	}
	
	for ( k = 2 ; k < N ; ++k ){
		for ( i = 2 ; i + k <= N + 1; ++i ){
			bst[i][i+k] = Inf;
			for ( j = i  ; j < i + k ; ++j ){
				aux = bst[i][j] + bst[j+1][i+k] + d[i-1] * d[i+k] * d[j] ;
				if ( bst[i][i+k] > aux )
					bst[i][i+k] = aux;
			}
			
		}
		
	}
	g<<bst[2][N+1];
	
	return 0;
}