Pyramid #430
Generating function
$$U_{430}(x, y) = \frac{\sqrt{3} \left(\sqrt{3 x y + \sin^{2}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}} + \sin{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}\right)}{3 \sqrt{y}}$$
Explicit formula
$$T_{430}(n, m, k) = \begin{cases}1&\text{if n=0 and m=0} ,\ \\\frac{k {\binom{k + 3 m - 1}{m}}}{k + 2 m}&\text{if n=0} ,\ \\\frac{\left(-1\right)^{n - 1} k {\binom{- k + 2 n - 1}{n - 1}}}{n}&\text{if m=0} ,\ \\\frac{\left(-1\right)^{m - 1} k \left(k - 2 n\right) {\binom{k - n - 1}{n - 1}} {\binom{- k - 2 m + 2 n - 1}{m - 1}}}{m n}&\text{if m>0} \end{cases} $$
Data table
1 1 3 12 55 273 1428
1 -1 -2 -7 -3 -143 -728
-1 3 3 1 42 198 1001
2 -1 0 -1 -5 -252 -132
-5 35 -35 0 35 245 147
14 -126 252 -42 0 -126 -1176
-42 462 -1386 924 0 0 462
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