Pyramid #31
Generating function
$$U_{31}(x, y) = \frac{y}{\left(1 - x\right)^{3}} + \frac{1}{1 - x}$$
Explicit formula
$$T_{31}(n, m, k) = {\binom{k}{m}} {\binom{k + 2 m + n - 1}{n}}$$
Data table
1 1 0 0 0 0 0
1 3 0 0 0 0 0
1 6 0 0 0 0 0
1 1 0 0 0 0 0
1 15 0 0 0 0 0
1 21 0 0 0 0 0
1 28 0 0 0 0 0
Export
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