Pyramid #447
Generating function
$$U_{447}(x, y) = \frac{1}{\left(1 - x\right)^{2} \left(1 - y\right)^{3}}$$
Explicit formula
$$T_{447}(n, m, k) = {\binom{2 k + n - 1}{n}} {\binom{3 k + m - 1}{m}}$$
Data table
1 3 6 1 15 21 28
2 6 12 2 3 42 56
3 9 18 3 45 63 84
4 12 24 4 6 84 112
5 15 3 5 75 105 14
6 18 36 6 9 126 168
7 21 42 7 105 147 196
Export
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