#include <bits/stdc++.h>

using namespace std;
int n,k;
int euclid(int a,int b){
    if (b==0) return a;
     else return euclid(b,a%b);



}

int main()

{
ifstream in("fractii.in");
ofstream out("fractii.out");

    bool sita[1000001];
    int i,j;



    cin>>n;

    for (i=2;i<=n;i++){
        if (sita[i])
            for (j=i+i;j<=n;j+=i) sita[j]=true;

    }

    k=n;
    for (int i=2;i<=n;i++)
        for (int j=2;j<=n;j++){
            if (i==j) k++;
            else if (sita[i] || sita[j]) k++;
            else if (euclid(i,j)==1) k++;


        }

    cout<<k;


    return 0;
}