#include <iostream>
#include <fstream>
using namespace std;
ifstream in("fractii.in");
ofstream out("fractii.out");
/*int simplificat(int b, int v)
{
    int m,inter;
    if(b<v) { inter=b; b=v; v=inter; }
    for(m=2;m<=b;m++)
        if(b%m==0)
            if(v%m==0) return 1;
    return 0;
}*/

int cmmdc(int a,int b)
{
    while(a!=b)
    if(a<b) b=b-a;
    else a=a-b;
    return b;
}

int n,nfinal,i,j;
int main()
{
    in >> n;
    nfinal=2*n-1;
    for(i=2;i<=n;i++)
        {
            for(j=2;j<=i;j++)
            {
                //if(i%j!=0 && j%i!=0 && simplificat(i,j)==0) nfinal++;
                if(i%j!=0)
                    if(j%i!=0)
                        /*if (simplificat(i,j)==0) nfinal++;*/
                        if (cmmdc(i,j)==1) nfinal+=2;
            }
        }
    out << nfinal;
    return 0;
}