Pyramid #314
Generating function
$$U_{314}(x, y) = x + \frac{\sqrt{\frac{4 x}{\left(1 - y\right)^{2}} + \frac{1}{\left(1 - y\right)^{4}}}}{2} + \frac{1}{2 \left(1 - y\right)^{2}}$$
Explicit formula
$$T_{314}(n, m, k) = \begin{cases}{\binom{2 k + m - 1}{m}}&\text{if n=0} ,\ \\\frac{2 \left(-1\right)^{n - 1} k {\binom{- 2 k + 2 n - 1}{n - 1}} {\binom{2 k + m - 2 n - 1}{m}}}{n}&\text{if n>0} \end{cases} $$
Data table
1 2 3 4 5 6 7
2 0 0 0 0 0 0
-1 2 -1 0 0 0 0
2 -8 12 -8 2 0 0
-5 3 -75 1 -75 3 -5
14 -112 392 -784 98 -784 392
-42 42 -189 504 -882 10584 -882
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