Pyramid #497
Generating function
$$U_{497}(x, y) = \frac{\left(1 - y\right)^{2} \left(1 - \sqrt{- \frac{4 x}{\left(1 - y\right)^{3}} + 1}\right)}{2 x}$$
Explicit formula
$$T_{497}(n, m, k) = \frac{k {\binom{k + 2 n}{n}} {\binom{k + m + 3 n - 1}{m}}}{k + 2 n}$$
Data table
1 1 1 1 1 1 1
1 4 1 2 35 56 84
2 14 56 168 42 924 1848
5 5 275 11 3575 1001 25025
14 182 1274 637 2548 86632 259896
42 672 5712 34272 162792 651168 2279088
132 2508 2508 17556 96558 4441668 17766672
Export
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