Pyramid #729
Generating function
$$U_{729}(x, y) = x^{2} \left(y + 1\right)^{3} + 2 x \left(y + 1\right)^{2} + y + 1$$
Explicit formula
$$T_{729}(n, m, k) = {\binom{2 k}{n}} {\binom{k + n}{m}}$$
Data table
1 1 0 0 0 0 0
2 4 2 0 0 0 0
1 3 3 1 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
Export
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