#include <bits/stdc++.h>
using namespace std;
#define int long long
#define ld long double
int32_t main(){
    ld n;
    cin>>n;
    int ans=0;
    for(int i=0;i<10;i++){
        for(int j=0;j<10;j++){
            if(i==j)continue;
            int limit=max(i,j)+1;
            // ld p1=((ld)n*i+sqrt((ld)n*n*i*i+(ld)4.0*((ld)1.0+n*j)))/(ld)2.0;
            int high,low;
            high=1e9+1;
            low=0;
            while(high-low>1){
                int mid=(high+low)/2;
                int f=mid*mid-n*i*mid-1-n*j;
                if(f<0){
                    low=mid;
                }else{
                    high=mid;
                }
            }
            // int x1=(int)p1;
            int x1=low;
            if(x1<limit)continue;
            ans+=min((int)1e9,x1)-limit+1;
        }
    }
    cout<<ans<<endl;
}