Pyramid #579
Generating function
$$U_{579}(x, y) = \frac{y^{6} \left(4 - 4 \sqrt{- \frac{x \left(- 2 y - \sqrt{1 - 4 y} + 1\right)^{4}}{4 y^{8}} + 1}\right)}{x \left(- 2 y - \sqrt{1 - 4 y} + 1\right)^{3}}$$
Explicit formula
$$T_{579}(n, m, k) = \frac{k \left(k + 4 n\right) {\binom{k + 2 n - 1}{n}} {\binom{2 k + 2 m + 8 n}{m}}}{\left(k + n\right) \left(k + m + 4 n\right)}$$
Data table
1 2 5 14 42 132 429
1 1 65 35 17 7752 33915
2 36 378 3036 207 12636 71253
5 13 1885 2015 17732 136136 9444435
14 476 8806 117572 126854 11748632 96926214
42 1764 3969 635628 8124984 8816472 84368739
132 66 1749 3267 48279 60076632 65440617
Export
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