Strong tiling#1863
A tiling of an m \times n rectangle with dominoes is called strong if there does not exist a straight line that passes through the interior of the m \times n rectangle and avoids the interior of every domino.
For example, in the illustration, tilings (a) and (b) are strong, while tilings (c) and (d) are not.
How many strong tilings are there of an m \times n rectangle?
The first line contains two positive integers and (1 \leq m \leq 8; 1 \leq n \leq 16) — the width and height of the board.
Print the number of strong tilings of the given rectangle.
Example 1
All strong tilings of a 5 \times 6 rectangle are shown below:
