#include <iostream>
#include <fstream>

using namespace std;

int cmmdc(int a,int b){

	int r;

	r=a%b;

	while(r>0)
	{
	a=b;
	b=r;
	r=a%b;
	}

	return b;

}

int main(){

	int n,p,q,i=0;

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

	fin >> n;

	for(p=1;p<=n;p++){
		for(q=1;q<=n;q++){
			if(cmmdc(p,q)==1){
				cout << p << "/" << q << endl;
				i++;
			}
		}
	}

	fout << i;

	return 0;
}