Generating function
$$U_{432}(x, y) = \sqrt[3]{\frac{x}{2} + \frac{\sqrt{3} \sqrt{x \left(27 x + \frac{32 \sqrt{3} \sin^{3}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}}{9 y^{\frac{3}{2}}}\right)}}{18} + \frac{8 \sqrt{3} \sin^{3}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}}{243 y^{\frac{3}{2}}}} + \frac{4 \sin^{2}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}}{27 y \sqrt[3]{\frac{x}{2} + \frac{\sqrt{3} \sqrt{x \left(27 x + \frac{32 \sqrt{3} \sin^{3}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}}{9 y^{\frac{3}{2}}}\right)}}{18} + \frac{8 \sqrt{3} \sin^{3}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}}{243 y^{\frac{3}{2}}}}} + \frac{2 \sqrt{3} \sin{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}}{9 \sqrt{y}}$$
Explicit formula
$$T_{432}(n, m, k) = \begin{cases}1&\text{if n=0 and m=0} ,\ \\\frac{k {\binom{k + 3 m - n - 1}{m}}}{k + 2 m}&\text{if n=0} ,\ \\\frac{\left(-1\right)^{n - 1} k {\binom{- k + 3 n - 1}{n - 1}}}{n}&\text{if m=0} ,\ \\\frac{\left(-1\right)^{m - 1} k \left(k - 3 n\right) {\binom{k - 2 n - 1}{n - 1}} {\binom{- k - 2 m + 3 n - 1}{m - 1}}}{m n}&\text{if m>0} \end{cases} $$
1 | 1 | 3 | 12 | 55 | 273 | 1428 |
1 | -2 | -3 | -1 | -42 | -198 | -1001 |
-2 | 1 | 0 | 1 | 5 | 252 | 132 |
7 | -56 | 84 | 0 | -14 | -168 | -1176 |
-3 | 33 | -99 | 66 | 0 | 0 | 33 |
143 | -2002 | 9009 | -14014 | 5005 | 0 | 0 |
-728 | 12376 | -74256 | 18564 | -173264 | 37128 | 0 |
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