Pyramid #47
Generating function
$$U_{47}(x, y) = \frac{y + \sqrt{- 4 x + y^{2} + y \left(4 x - 2\right) + 1} - 1}{2 x \left(y - 1\right)}$$
Explicit formula
$$T_{47}(n, m, k) = \frac{k {\binom{k + m + n}{m}} {\binom{k + 2 n - 1}{n}}}{k + m + n}$$
Data table
1 1 1 1 1 1 1
1 2 3 4 5 6 7
2 6 12 2 3 42 56
5 2 5 1 175 28 42
14 7 21 49 98 1764 294
42 252 882 2352 5292 10584 19404
132 924 3696 11088 2772 60984 121968
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