/*
TASK: necklace
LANG: C++
*/
#include<iostream>
int rez();
using namespace std;
int del[21]={0,3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60},n,ne4,che,sum,x=0,y=0;
int main(){
    int i=0,sum[21],sum1=0,pos,j;
    cin>>n;
    while(del[i]<n){ sum[i]=del[i];i++;}
    
    pos=i-1;
     for(i=0;i<pos;i++){
        for(j=1;j<=n/2;j++){
            ne4=n/2-1;
            che=n/2; y=j;
        x=abs(sum[i]+y);
        if(x<=n/2){
            sum1+=rez();
        }
        else if(y==1 && x>n/2){ y=0;
        x=sum[i];
        sum1+=rez();
        }
    }
}//for
cout<<sum1<<endl;
system("pause");
return 0;
}
int rez(){
    int i,j;
    if(y==0) return (ne4)/(x);
    if(x==1) return  che/(y+1);
    else return (ne4*(x))*(che/(y));
    return 0;
}
    
    

    
        
    
                   
