Pyramid #308
Generating function
$$U_{308}(x, y) = - \frac{\left(1 - \sqrt{1 - 4 y}\right)^{2}}{y^{2} \left(4 x - \frac{2 - 2 \sqrt{1 - 4 y}}{y}\right)}$$
Explicit formula
$$T_{308}(n, m, k) = \begin{cases}{\binom{k + n - 1}{n}}&\text{if m=0} ,\ \\\frac{\left(-1\right)^{m - 1} \left(k - n\right) {\binom{k + n - 1}{n}} {\binom{- k - m + n - 1}{m - 1}}}{m} \end{cases} $$
Data table
1 1 2 5 14 42 132
1 0 0 0 0 0 0
1 -1 -1 -2 -5 -14 -42
1 -2 -1 -2 -5 -14 -42
1 -3 0 -1 -3 -9 -28
1 -4 2 0 -1 -4 -14
1 -5 5 0 0 -1 -5
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