Generating function
$$U_{1477}(x, y) = \frac{2 \sqrt{3} \sin{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{\frac{x}{\left(1 - y\right)^{3}}}}{2} \right)}}{3} \right)}}{3 \sqrt{\frac{x}{1 - y}} \left(1 - y\right)}$$
Explicit formula
$$T_{1477}(n, m, k) = \frac{k {\binom{k + 3 n - 1}{n}} {\binom{3 k + m + 3 n - 1}{m}}}{k + 2 n}$$
Data table
1 3 6 1 15 21 28
1 6 21 56 126 252 462
3 27 135 495 1485 3861 9009
12 144 936 4368 1638 52416 148512
55 825 66 374 1683 63954 21318
273 4914 46683 31122 1633905 7189182 27558531
1428 29988 329868 2528988 15173928 7586964 32876844
Export
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