#include <iostream>
#include <fstream>
using namespace std;

int cmmdc(int a, int b)
{
    for(int i=2; i<=min(a,b); i++)
    {
        if(a%i==0 && b%i==0)
        {
            return i;
        }
    }
    return 1;
}

int main ()
{
    ifstream read("fractii.in");
    ofstream write("fractii.out");
    int n;

    read>>n;
    int count = 2*n - 1, count2=0;
    for(int i=2; i<=n; i++)
    {
        for(int j=i+1; j<=n; j++)
        {
            if(cmmdc(i,j)==1)
            {
                count2++;
            }
        }
    }
    count +=2*count2;
    write<<count;

    return 0;
}