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