Pyramid #82
Generating function
$$U_{82}(x, y) = \frac{1 - \sqrt{y \left(- 4 x^{4} - 16 x^{3} - 24 x^{2} - 16 x - 4\right) + 1}}{2 y \left(x + 1\right)^{2}}$$
Explicit formula
$$T_{82}(n, m, k) = \frac{k {\binom{2 k + 4 m}{n}} {\binom{k + 2 m - 1}{m}}}{k + m}$$
Data table
1 1 2 5 14 42 132
2 6 2 7 252 924 3432
1 15 9 455 2142 9702 429
0 2 24 182 11424 6468 3432
0 15 42 5005 4284 30723 19734
0 6 504 1001 119952 1106028 868296
0 1 42 15015 259896 3133746 3039036
Export
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