Pyramid #829
Generating function
$$U_{829}(x, y) = \frac{1 - \sqrt{- 4 x y^{5} - 20 x y^{4} - 40 x y^{3} - 40 x y^{2} - 20 x y - 4 x + 1}}{2 x y + 2 x}$$
Explicit formula
$$T_{829}(n, m, k) = \frac{k {\binom{4 k + 5 n}{m}} {\binom{k + 2 n - 1}{n}}}{k + n}$$
Data table
1 4 6 4 1 0 0
1 9 36 84 126 126 84
2 28 182 728 2002 4004 6006
5 95 855 4845 1938 5814 13566
14 336 3864 28336 148764 595056 1884344
42 1218 17052 153468 997542 498771 1995084
132 4488 74052 789888 6121632 36729792 177527328
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