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2402.   Lattice Animals
Time Limit: 6.0 Seconds   Memory Limit: 65536K
Total Runs: 40   Accepted Runs: 13    Multiple test files
Case Time Limit: 3.0 Seconds



Lattice animal is a set of connected sites on a lattice. Lattice animals on a square lattice are especially popular subject of study and are also known as polyominoes. Polyomino is usually represented as a set of sidewise connected squares. Polyomino with n squares is called n-polyomino.

In this problem you are to find a number of distinct free n-polyominoes that fit into rectangle w × h. Free polyominoes can be rotated and flipped over, so that their rotations and mirror images are considered to be the same.

For example, there are 5 different pentominoes (5-polyominoes) that fit into 2 × 4 rectangle and 3 different octominoes (8-polyominoes) that fit into 3 × 3 rectangle.

Input

The input consists of a single line with 3 integer numbers n, w, and h (1 ≤ n ≤ 10, 1 ≤ w, hn).

Output

Write to the output a single integer number — the number of distinct free n-polyominoes that fit into rectangle w × h.

Sample InputSample Output
5 1 40
5 2 45
5 3 411
5 5 512
8 3 33



Source: Northeastern European 2004
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