Pyramid #560
Generating function
$$U_{560}(x, y) = \frac{1 - \frac{4 \sin^{2}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{- x}}{2} \right)}}{3} \right)}}{3}}{1 - y}$$
Explicit formula
$$T_{560}(n, m, k) = \begin{cases}{\binom{k + m - 1}{m}}&\text{if n==0} ,\ \\\frac{\left(-1\right)^{n - 1} k {\binom{- k + 3 n - 1}{n - 1}} {\binom{k + m - 1}{m}}}{n}&\text{if n>0} \end{cases} $$
Data table
1 1 1 1 1 1 1
1 1 1 1 1 1 1
-2 -2 -2 -2 -2 -2 -2
7 7 7 7 7 7 7
-3 -3 -3 -3 -3 -3 -3
143 143 143 143 143 143 143
-728 -728 -728 -728 -728 -728 -728
Export
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