Pyramid #832
Generating function
$$U_{832}(x, y) = \frac{- y^{2} + 2 y + \sqrt{- 4 x + y^{4} - 4 y^{3} + 6 y^{2} - 4 y + 1} - 1}{2 x y - 2 x}$$
Explicit formula
$$T_{832}(n, m, k) = \frac{k {\binom{k + 2 n - 1}{n}} {\binom{3 k + m + 4 n - 1}{m}}}{k + n}$$
Data table
1 3 6 1 15 21 28
1 7 28 84 21 462 924
2 22 132 572 2002 6006 16016
5 75 6 34 153 5814 1938
14 266 266 1862 10241 471086 1884344
42 966 11592 966 6279 339066 1582308
132 3564 49896 482328 361746 22428252 119617344
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