#include <fstream>
#include<bits/stdc++.h> 

using namespace std;

/***************/

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

int numar;

/***************/

int rezolva()
{
	int ans = 0;
	numar = numar+1;
	for(int i = 1; i < numar; i++)
	{
		for(int j = 1; j < numar; j++)
		{
			if (__gcd(i, j) == 1)
			{
				ans++;
			}
		}
	}
	return ans;
}


#include <iostream>
int main(int argc, char *argv[], char* env[])
{
	fin >> numar;
	fout << rezolva();

	return 0;
}