#include <fstream>

using namespace std;

const char InFile[]="podm.in";
const char OutFile[]="podm.out";
const unsigned long long MaxN=505;
const unsigned long long INF=(1LL<<60);

ifstream fin(InFile);
ofstream fout(OutFile);

unsigned long long N,d[MaxN],best[MaxN][MaxN];

int main()
{
	fin>>N;
	for(register int i=0;i<=N;++i)
	{
		fin>>d[i];
	}
	fin.close();

	for(register int i=1;i<N;++i)
	{
		best[i][i+1]=d[i-1]*d[i]*d[i+1];
	}

	for(register int k=2;k<=N;++k)
	{
		for(register int i=1;i+k<=N;++i)
		{
			best[i][i+k]=INF;
			for(register int j=i;j<i+k;++j)
			{
				best[i][i+k]=min(best[i][i+k],best[i][j]+best[j+1][i+k]+d[i-1]*d[i+k]*d[j]);
			}
		}
	}

	fout<<best[1][N];
	fout.close();
	return 0;
}