$$U_{306}(x, y) = - \frac{4 \sin^{2}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}}{y \left(3 x - \frac{2 \sqrt{3} \sin{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}}{\sqrt{y}}\right)}$$

$$T_{306}(n, m, k) = \begin{cases}1&\text{if m=0} ,\ \\\frac{\left(-1\right)^{m - 1} \left(k - n\right) {\binom{k + n - 1}{n}} {\binom{- k - 2 m + n - 1}{m - 1}}}{m}&\text{if m>0} \end{cases} $$