#include <iostream>
#include <vector>
#include <iomanip>
typedef unsigned long long ul;
typedef signed long long ll;

int main(void)
{
  std::cin.tie(0);
  std::ios::sync_with_stdio(false);
  std::cout << std::fixed << std::setprecision(15);
  std::vector< int > prime = {2, 3, 5, 7, 11, 13};
  std::vector< int > comp = {4, 6, 8, 9, 10, 12};
  int k;
  std::cin >> k;
  int cnt = 0;
  for (auto p : prime) {
    for (auto c : comp) {
      if (k == p * c) cnt++;
    }
  }
  std::cout << cnt / 36.0 << std::endl;
  return 0;
}