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