#include <iostream>
#include <fstream>

using namespace std;

ifstream fin("fractii.in");
ofstream fout("fractii.out");

bool FractieIreductibila(int x, int y) {
    while(x!=y)
        if(x>y) x-=y;
        else y-=x;
    if(x==1) return true;
    return false;
}

int main()
{
    int n,contor;
    fin>>n;
    contor=2*n-1;
    for(int i=2; i<=n; i++)
        for(int j=i+1; j<=n; j++)
            if(FractieIreductibila(i,j))
                contor+=2;
    fout<<contor;
    return 0;
}