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