Pyramid #284
Generating function
$$U_{284}(x, y) = \frac{2 \sqrt{3} \left(y + 1\right) \sin{\left(\frac{\arcsin{\left(\frac{3 \sqrt{3} \sqrt{x}}{2} \right)}}{3} \right)}}{3 \sqrt{x}}$$
Explicit formula
$$T_{284}(n, m, k) = \frac{k {\binom{k}{m}} {\binom{k + 3 n - 1}{n}}}{k + 2 n}$$
Data table
1 1 0 0 0 0 0
1 1 0 0 0 0 0
3 3 0 0 0 0 0
12 12 0 0 0 0 0
55 55 0 0 0 0 0
273 273 0 0 0 0 0
1428 1428 0 0 0 0 0
Export
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