Pyramid #563
Generating function
$$U_{563}(x, y) = - \frac{1}{\left(1 - y\right) \left(\frac{x}{\left(1 - y\right)^{3}} - 1\right)}$$
Explicit formula
$$T_{563}(n, m, k) = {\binom{k + n - 1}{n}} {\binom{k + m + 3 n - 1}{m}}$$
Data table
1 1 1 1 1 1 1
1 4 1 2 35 56 84
1 7 28 84 21 462 924
1 1 55 22 715 2002 5005
1 13 91 455 182 6188 18564
1 16 136 816 3876 15504 54264
1 19 19 133 7315 33649 134596
Export
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