Pyramid #564
Generating function
$$U_{564}(x, y) = \frac{\left(1 - y\right)^{3} \left(1 - \sqrt{- \frac{4 x}{\left(1 - y\right)^{4}} + 1}\right)}{2 x}$$
Explicit formula
$$T_{564}(n, m, k) = \frac{k {\binom{k + 2 n - 1}{n}} {\binom{k + m + 4 n - 1}{m}}}{k + n}$$
Data table
1 1 1 1 1 1 1
1 5 15 35 7 126 21
2 18 9 33 99 2574 6006
5 65 455 2275 91 3094 9282
14 238 2142 13566 6783 284886 1044582
42 882 9702 74382 446292 223146 966966
132 33 429 3861 27027 1567566 783783
Export
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