Pyramid #775
Generating function
$$U_{775}(x, y) = \frac{4 \left(y + 1\right)^{2} \sin^{2}{\left(\frac{\arcsin{\left(\frac{3 \sqrt{3} \sqrt{x}}{2} \right)}}{3} \right)}}{3 x}$$
Explicit formula
$$T_{775}(n, m, k) = \frac{k {\binom{2 k}{m}} {\binom{2 k + 3 n - 1}{n}}}{k + n}$$
Data table
1 2 1 0 0 0 0
2 4 2 0 0 0 0
7 14 7 0 0 0 0
3 6 3 0 0 0 0
143 286 143 0 0 0 0
728 1456 728 0 0 0 0
3876 7752 3876 0 0 0 0
Export
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