Pyramid #666
Generating function
$$U_{666}(x, y) = \frac{\sqrt{4 x \left(y + 1\right)^{2} + 1} - 1}{2 x}$$
Explicit formula
$$T_{666}(n, m, k) = \frac{\left(-1\right)^{n} k {\binom{2 k + 2 n}{m}} {\binom{k + 2 n - 1}{n}}}{k + n}$$
Data table
1 2 1 0 0 0 0
-1 -4 -6 -4 -1 0 0
2 12 3 4 3 12 2
-5 -4 -14 -28 -35 -28 -14
14 14 63 168 294 3528 294
-42 -504 -2772 -924 -2079 -33264 -38808
132 1848 12012 48048 132132 264264 396396
Export
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