11351: Tri Tiling
Memory Limit:128 MB
Time Limit:1.000 S
Judge Style:Text Compare
Creator:
Submit:1
Solved:0
Description

In how many ways can you tile a 3xn rectangle with 2x1 dominoes?
Here is a sample tiling of a 3x12 rectangle.

Input consists of several test cases followed by a line containing -1. Each test case is a line containing an integer 0 ≤ n ≤ 30. For each test case, output one integer number giving the number of possible tilings.
Sample Input Copy
2
8
12
-1
Sample Output Copy
3
153
2131