Pyramid #258
Generating function
$$U_{258}(x, y) = \frac{2 x y - y - \sqrt{- 4 x y + y^{2} + 2 y + 1} - 1}{2 x - 2}$$
Explicit formula
$$T_{258}(n, m, k) = \begin{cases}{\binom{k}{m}}&\text{if n=0} ,\ \\\frac{\left(-1\right)^{m - n - 1} k {\binom{- k + m - 1}{n - 1}} {\binom{- k + m + n}{m}}}{n} \end{cases} $$
Data table
1 1 0 0 0 0 0
1 -1 1 -1 1 -1 1
1 -1 0 2 -5 9 -14
1 -1 0 0 5 -21 56
1 -1 0 0 0 14 -84
1 -1 0 0 0 0 42
1 -1 0 0 0 0 0
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