def find_beautiful_number(n): if n == 1: return 3 count = 1 # 已经找到的第一个美丽数的计数 num = 3 # 从最小的美丽数3开始 while True: num += 1 if num % 3 == 0 or num % 5 == 0: count += 1 if count == n: return num while True: try: n = int(input()) print(find_beautiful_number(n)) except : break