Game

You are designing a video game of the classic shoot’em up genre. The player controls a spaceship moving in an environment that continuously scrolls from top to bottom, giving a sense of flying forward. The ship has to fight hoards of enemies to reach the end of each stage.

In this problem you have to decide how many enemies to populate each stage with. The first stage always contains 10 enemies. At each subsequent stage $n>1$ , the number of enemies $E(n)$ is the minimum number divisible by $n$ such that $E(n)\geq 2E(n-1)$ .

Input

The input consists of several test cases. Each test case consists of a single integer $1\leq N\leq 61$ , representing the total number of stages of the game.

Output

For each test case, a number on a single line representing the number of enemies on the last stage $N$ .

Problem information

Author: Anders Jonsson

Generation: 2026-01-25T21:47:09.362Z