Pyramid #574
Generating function
$$U_{574}(x, y) = \frac{y^{3} \left(4 - 4 \sqrt{- \frac{x \left(1 - \sqrt{1 - 4 y}\right)^{4}}{4 y^{4}} + 1}\right)}{x \left(1 - \sqrt{1 - 4 y}\right)^{3}}$$
Explicit formula
$$T_{574}(n, m, k) = \frac{k \left(k + 4 n\right) {\binom{k + 2 n - 1}{n}} {\binom{k + 2 m + 4 n - 1}{m}}}{\left(k + n\right) \left(k + m + 4 n\right)}$$
Data table
1 1 2 5 14 42 132
1 5 2 75 275 1001 364
2 18 108 546 252 11016 46512
5 65 52 3315 18525 95095 46046
14 238 238 18326 120428 71162 389844
42 882 10584 9555 722358 4834242 29602272
132 33 462 4785 4092 3060816 2073456
Export
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