Generating function
$$U_{1272}(x, y) = \frac{\left(1 - \sqrt{- 4 x \left(y + 1\right)^{3} + 1}\right)^{2}}{4 x^{2} \left(y + 1\right)^{3}}$$
Explicit formula
$$T_{1272}(n, m, k) = \frac{2 k {\binom{3 k + 3 n}{m}} {\binom{2 k + 2 n - 1}{n}}}{2 k + n}$$
Data table
1 3 3 1 0 0 0
2 12 3 4 3 12 2
5 45 18 42 63 63 42
14 168 924 308 693 11088 12936
42 63 441 1911 5733 126126 21021
132 2376 20196 107712 40392 1130976 2450448
429 9009 9009 57057 2567565 8729721 23279256
Export
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