#include<fstream>
using namespace std;

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

int cmmdc(int a,int b)
{
    while(b)
    {
        int r=a%b;
        a=b;
        b=r;
    }
    return a;
}
int main()
{
    int n,i,j;
    long long k;
    fin>>n;
    k=2*n-1;
    for(i=2;i<=n;i++)
        for(j=2;j<=n;j++)
        {
            if(cmmdc(i,j)==1)
                k++;
        }
    fout<<k;
}