#include <iostream>
#include<fstream>
using namespace std;
long cmmdc(long unsigned a,long unsigned b)
{
    while(a!=b)
    {
        if(a>b)
            a=a-b;
        else
            b=b-a;
    }
    return a;
}
long prim(long n)
{
    int k=0;
    long i;
    for(i=1;i<=n;i++)
    {
        if(cmmdc(i,n)==1)
            k++;
    }
    return k;
}
int main()
{
    ifstream f("fractii.in");
    ofstream g("fractii.out");
    int s,i;
    long unsigned n;
    f>>n;
    s=0;
    for(i=1;i<=n;i++)
        s=s+prim(i);
   g<<2*s-1;
    return 0;
}