Pyramid #365
Generating function
$$U_{365}(x, y) = \frac{y}{3} + \frac{\left(y + 1\right)^{2}}{9 \sqrt[3]{\frac{x}{2} + \frac{\sqrt{3} \sqrt{x \left(27 x + 4 \left(y + 1\right)^{3}\right)}}{18} + \frac{\left(y + 1\right)^{3}}{27}}} + \sqrt[3]{\frac{x}{2} + \frac{\sqrt{3} \sqrt{x \left(27 x + 4 \left(y + 1\right)^{3}\right)}}{18} + \frac{\left(y + 1\right)^{3}}{27}} + \frac{1}{3}$$
Explicit formula
$$T_{365}(n, m, k) = \begin{cases}1&\text{if n+m=0} ,\ \\\frac{k {\binom{m + n}{m}} {\binom{k - 2 n - 1}{m + n - 1}}}{m + n} \end{cases} $$
Data table
1 1 0 0 0 0 0
1 -2 3 -4 5 -6 7
-2 1 -3 7 -14 252 -42
7 -56 252 -84 231 -5544 12012
-3 33 -198 858 -3003 9009 -24024
143 -2002 15015 -8008 34034 -1225224 3879876
-728 12376 -111384 705432 -352716 14814072 -54318264
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