#include <bits/stdc++.h>
using namespace std;
const int N=55;
__int128 a[2*N], f[2*N][2*N];
template<typename T>void qr(T& x)
{
    x=0;int f=1;char c=getchar();
    for( ;!isdigit(c);c=getchar())if(c=='-')f=-1;
    for( ; isdigit(c);c=getchar())x=x*10+c-48;
    x=x*f;
}
template<typename T>void qw(T x)
{
    if(x<0)x=-x,putchar('-');
    if(x/10)qw(x/10);
    putchar(x%10+48); 
}
int main()
{
    int n;scanf("%d", &n);
    for(int i=1;i<=n;i++)qr(a[i]),a[i+n]=a[i];
    memset(f, 63, sizeof(f));
    for(int k=1;k<=n;k++)
        for(int i=1;i<=2*n-k;i++)
        {
            int j=i+k-1;
            if(k<=2){f[i][j]=0;continue;}
            for(int l=i+1;l<=j-1;l++)
                f[i][j]=min(f[i][j],f[i][l]+f[l][j]+a[i]*a[j]*a[l]);
        }
    __int128 ans=__int128(1)<<120;
    for(int i=1;i<=n;i++) ans=min(ans,f[i][i+n-1]);
    qw(ans);
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
const int N=55;
__int128 a[2*N],f[2*N][2*N];
template<typename T>void qr(T& x)
{
	x=0;int f=1;char c=getchar();
	for( ;!isdigit(c);c=getchar())if(c=='-')f=-1;
	for( ; isdigit(c);c=getchar())x=x*10+c-48;
	x=x*f;
}
template<typename T>void qw(T x)
{
	if(x<0)x=-x,putchar('-');
	if(x/10)qw(x/10);
	putchar(x%10+48); 
}
int main()
{
	int n;scanf("%d",&n);
	for(int i=1;i<=n;i++)qr(a[i]),a[i+n]=a[i];
	memset(f,63,sizeof(f));
	for(int k=1;k<=n;k++)
		for(int i=1;i<=2*n-k;i++)
		{
			int j=i+k-1;
			if(k<=2){f[i][j]=0;continue;}
			for(int l=i+1;l<=j-1;l++)
				f[i][j]=min(f[i][j],f[i][l]+f[l][j]+a[i]*a[j]*a[l]);
		}
	__int128 ans=__int128(1)<<120;
	for(int i=1;i<=n;i++) ans=min(ans,f[i][i+n-1]);
	qw(ans);
    return 0;
}