Generating function
$$U_{1097}(x, y) = \frac{\left(1 - \sqrt{1 - 4 y}\right)^{2} \left(- 2 x - \sqrt{1 - 4 x} + 1\right)^{3}}{32 x^{6} y^{2}}$$
Explicit formula
$$T_{1097}(n, m, k) = \frac{6 k^{2} {\binom{6 k + 2 n}{n}} {\binom{2 k + 2 m - 1}{m}}}{\left(2 k + m\right) \left(3 k + n\right)}$$
Data table
1 2 5 14 42 132 429
6 12 3 84 252 792 2574
27 54 135 378 1134 3564 11583
11 22 55 154 462 1452 4719
429 858 2145 6006 18018 56628 184041
1638 3276 819 22932 68796 216216 702702
6188 12376 3094 86632 259896 816816 2654652
Export
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