#include <iostream>
#include <fstream>
using namespace std;
int cm(long j, long i)
{
    long c;
    while(j%i!=0)
    {
        c=j%i; j=i; i=c;
    }
    return i;
}
int main()
{
    ifstream in("fractii.in");
    ofstream out("fractii.out");
    long n,i,j,f=0;
    in>>n;
    for(i=2;i<=n-1;i++)
        for(j=i+1;j<=n;j++) {if(cm(j,i)==1) f++;}
        f=f*2+2*n-1;
    out<<f;
    return 0;
}