#include <bits/stdc++.h>

using namespace std;

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

void usain_bolt()
{
    ios::sync_with_stdio(false);
    fin.tie(0);
}

int main()
{
    usain_bolt();

    int n;

    fin >> n;

    if(n == 2) {
        fout << "1" << " " << "1" << "\n" << "1" << "\n" << "1";
        return 0;
    }
    fout << n << " " << "2" << "\n";
    for(int i = 1; i < n; ++i) {
        fout << i << " " << i + 1 << "\n";
    }
    fout << n << " " << 1;
    return 0;
}