Pyramid #45
Generating function
$$U_{45}(x, y) = \frac{x y - \sqrt{x^{2} y^{2} - 2 x y - 4 x + 1} + 1}{2 x}$$
Explicit formula
$$T_{45}(n, m, k) = \frac{k {\binom{k + n}{m}} {\binom{k - m + 2 n - 1}{n}}}{k + n}$$
Data table
1 1 0 0 0 0 0
1 1 0 0 0 0 0
2 3 1 0 0 0 0
5 1 6 1 0 0 0
14 35 3 1 1 0 0
42 126 14 7 15 1 0
132 462 63 42 14 21 1
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