/*
TASK: necklace
LANG: C++
*/
int o[60];
#include<iostream.h>
#include<math.h>
int main()
{
    int n,i,a,b,p,pp=0,q,qq=0,d=0;
    o[1]=1;
    cin>>n;
    for (i=2;i<=n;i++)
    {
        for (q=i;q<=n;q++)
        {
        for (a=q;a<=n;a++)
        {
            for (b=i;b<=a;b++)
            {
                o[b]=1;
            }   
            for (p=2;p<=n;p++)
            {
                if (p%2==0&&o[p]==1) pp++;
                else if (p%2!=0&&o[p]==1) qq++;
                if (p!=1) o[p]=0;
            }
            if (abs(pp-qq)%3==0) d++;
            pp=0;qq=0;          
        }
        }
    }
    cout<<d;
    system("pause");
    return 0;
}
