Let us assume for simplicity that a person lying in a sleeping bag inside a tent occupies a rectangle of size 1 \times m on the floor. Accordingly, the floor of a classic -person tent is a rectangle of size n \times m, where people are meant to lie parallel to the side whose length equals the person's height.
However, in practice, there are other, more complex ways to arrange people in an -person tent. Your task is to count the number of such ways. Ways that differ by symmetry or rotation are considered different. For example, when m = 2, there are ways to arrange three people in a three-person tent:

The input file contains two natural numbers and (2 \leq m \leq 10;\ 1 \leq n \leq 40).
Output the number of ways to arrange people in an -person tent.
Example 1