import sys; input = sys.stdin.buffer.readline
sys.setrecursionlimit(10**7)
from collections import defaultdict
con = 10 ** 9 + 7; INF = float("inf")

def getlist():
	return list(map(int, input().split()))

#処理内容
def main():
	K = int(input())
	dice1 = [2, 3, 5, 7, 11, 13]
	dice2 = [4, 6, 8, 9, 10, 12]
	num = [0] * 201
	for i in dice1:
		for j in dice2:
			num[i * j] += 1

	ans = num[K] / 36
	print(ans)
	



if __name__ == '__main__':
	main()