#include <bits/stdc++.h>
using namespace std;
int n, a[1000005];
int main() {
  cin >> n;
  int x = 0;
  int y = n;
  for (int i = 1; i < n; ++i) {
    if (i & 1) {
      a[x] = i;
      a[x + n - i] = i;
      ++x;
    } else {
      a[y] = i;
      a[y + n - i] = i;
      ++y;
    }
  }
  for (int i = 0; i < 2 * n; ++i) {
    if (a[i] == 0) a[i] = n;
    printf("%d ", a[i]);
  }
}
