Pyramid #934
Generating function
$$U_{934}(x, y) = \frac{1 - \sqrt{- 8 x y - 4 x \sqrt{4 y^{2} + 1} + 1}}{4 x y + 2 x \sqrt{4 y^{2} + 1}}$$
Explicit formula
$$Tsqrt2(n, k) = \begin{cases}\frac {k \binom{n+j}{n} \binom{2n+2j}{n+j}} {\binom{2j}{j} {n+k}} &\text{if n+k even, where j =} \frac{n+k} {2},\\\frac {k \binom{n+j}{n} \binom{2n+2j}{n+j}} {\binom{2j}{j} {n+k}} &\text{if n+k odd, where j =} \frac{n+k+1} {2},\\\end{cases} $$$$T_{934}(n, m, k) = \begin{cases}1&\text{if n=0 , m=0} ,\ \\\frac{k \operatorname{Tsqrt_{2}}{\left(m,n \right)} {\binom{k + 2 n}{n}}}{k + 2 n} \end{cases} $$
Data table
1 0 0 0 0 0 0
1 2 2 0 -2 0 4
2 8 16 16 0 -16 0
5 30 90 160 150 0 -140
14 112 448 1120 1792 1568 0
42 420 2100 6720 14700 21504 17640
132 1584 9504 36960 101376 199584 270336
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