#include <bits/stdc++.h>
using namespace std;
int N, n;
int main() {
  while (~scanf("%d", &N)) {
    n = N * N;
    for (int i = 0; i < N; i++) {
      for (int p = 1; p <= N / 2; p++) {
        printf("%d %d ", i * (N / 2) + p, n - (i * (N / 2) + p) + 1);
      }
      printf("\n");
    }
  }
  return 0;
}
