#include<fstream.h>
unsigned long long a[501][501],m;
int d[501],i,n,j,k,v[501];
int main()
{ifstream f("podm.in");
ofstream g("podm.out");
f>>n,a[0][0]=0;
for(i=0;i<=n;i++)
       f>>d[i],a[i][i]=0;
for(i=1;i<n;i++)
       a[i][i+1]=d[i-1]*d[i]*d[i+1];
for(j=2;j<n;j++)
for(i=1;i<=n-j;i++)
       {a[i][i+j]=1LL;
       for(k=i;k<i+j;k++)
       if(a[i][i+j]>(m=a[i][k]+a[k+1][i+j]+d[i-1]*d[k]*d[i+j]))
             a[i][i+j]=m;}
g<<a[1][n];
return 0;}