Pyramid #177
Generating function
$$U_{177}(x, y) = \frac{x}{2} + \frac{\left(x + 1\right) \sqrt{y \left(4 x + 4\right) + 1}}{2} + \frac{1}{2}$$
Explicit formula
$$T_{177}(n, m, k) = \begin{cases}{\binom{k}{n}}&\text{if m=0} ,\ \\\frac{\left(-1\right)^{m - 1} k {\binom{k + m}{n}} {\binom{- k + 2 m - 1}{m - 1}}}{m} \end{cases} $$
Data table
1 1 -1 2 -5 14 -42
1 2 -3 8 -25 84 -294
0 1 -3 12 -5 21 -882
0 0 -1 8 -5 28 -147
0 0 0 2 -25 21 -147
0 0 0 0 -5 84 -882
0 0 0 0 0 14 -294
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