Pyramid #547
Generating function
$$U_{547}(x, y) = \frac{y \left(3 x + \frac{8 \sqrt{3} \sin^{3}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}}{3 y^{\frac{3}{2}}}\right)}{4 \sin^{2}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}}$$
Explicit formula
$$T_{547}(n, m, k) = \begin{cases}{\binom{k}{n}}&\text{if m==0} ,\ \\\frac{\left(-1\right)^{m - 1} \left(k - 3 n\right) {\binom{k}{n}} {\binom{- k - 2 m + 3 n - 1}{m - 1}}}{m} \end{cases} $$
Data table
1 1 3 12 55 273 1428
1 -2 -3 -1 -42 -198 -1001
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
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