#include <iostream>
#include <fstream>
using namespace std;

int n, i, j;
int total;

int cmmdc(int a, int b){
if(b==0)
    return a;
else return cmmdc(b, a%b);
}

int main()
{
    ifstream fin ("fractii.in");
    ofstream fout ("fractii.out");
    fin >> n;
    total = n;
    for(i=2; i<=n;i++)
        for(j=1; j<=n; j++){
                if(cmmdc(j, i) == 1 || cmmdc(i, j)==1){
                    cout << i << "/" << j << "\n";
                    total++;
                }
        }
        fout << total;
return 0;
}