Generating function
$$U_{1073}(x, y) = \frac{\left(1 - \sqrt{1 - 4 x}\right)^{3} \left(- 2 y - \sqrt{1 - 4 y} + 1\right)^{3}}{64 x^{3} y^{6}}$$
Explicit formula
$$T_{1073}(n, m, k) = \frac{9 k^{2} {\binom{6 k + 2 m}{m}} {\binom{3 k + 2 n - 1}{n}}}{\left(3 k + m\right) \left(3 k + n\right)}$$
Data table
1 6 27 11 429 1638 6188
3 18 81 33 1287 4914 18564
9 54 243 99 3861 14742 55692
28 168 756 308 12012 45864 173264
9 54 243 99 3861 14742 55692
297 1782 8019 3267 127413 486486 1837836
1001 6006 27027 11011 429429 1639638 6194188
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