#include <fstream>
#include <iostream>
using namespace std;
int fi,fo,n,p,q,fcount;

int prime (int,int);

int main () 
{
	fstream fi("fractii.in",ios::in);
	fi>>n;
	fi.close();
	
	for (p=2; p<=n; p++)
		for (q=2; q<=n; q++)
		{
			//cout<<p<<"/"<<q<<"-"<<prime(p,q)<<endl;
			if (prime(p,q)==0) fcount++;
		}
	
	fcount+=n*2-1;
	fstream fo("fractii.out",ios::out);
	fo<<fcount;
	fo.close();
	//cout<<fcount;
	return 0;
}

int prime (int a,int b)
{
	if ((a%b)==0 && b!=1) return 1;
	else
	{
		int i,minim,gasit;
		gasit=0;
		if (a>b) minim=b;
		else minim=a;
		i=2;
		while (i<=minim && gasit==0) 
		{
			if ((a%i)==0 && (b%i)==0) gasit=1;
			i++;
		}
		return gasit;
	}
}