Pyramid #171
Generating function
$$U_{171}(x, y) = \frac{1}{x^{2} - 2 x + y \left(x - 1\right) + 1}$$
Explicit formula
$$T_{171}(n, m, k) = {\binom{k + m - 1}{m}} {\binom{2 k + m + n - 1}{n}}$$
Data table
1 1 1 1 1 1 1
2 3 4 5 6 7 8
3 6 1 15 21 28 36
4 1 2 35 56 84 12
5 15 35 7 126 21 33
6 21 56 126 252 462 792
7 28 84 21 462 924 1716
Export
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