#include<stdio.h>

long long a[6],n;

void citire()
{
freopen("12perm.in","r",stdin);
scanf("%ld",&n);
fclose(stdin);     
}     

void perm()
{
for (int i=4; i<n; i++)     
    {
    a[4]=a[i-1]+a[i-3]+2*(i-3);
    a[0]=a[1];
    a[1]=a[2];
    a[2]=a[3];
    a[3]=a[4];
    }
}     

void afisare(long long w)
{
freopen("12perm.out","w",stdout);
printf("%lld",w);
fclose(stdout);     
}     

int main()
{
citire();
a[0]=1;
a[1]=2;
a[2]=6;
a[3]=12;
if (n>4)
   {
   perm();
   afisare(a[4]);
   }
   else afisare(a[n-1]);
return 0;    
}