$$U_{288}(x, y) = \frac{\sqrt{3} \left(\sqrt{2 \sqrt{3} \sqrt{x} y \sin{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{x}}{2} \right)}}{3} \right)} + \sin^{2}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{x}}{2} \right)}}{3} \right)}} + \sin{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{x}}{2} \right)}}{3} \right)}\right)}{3 \sqrt{x}}$$

$$T_{288}(n, m, k) = \begin{cases}\frac{\left(-1\right)^{m - 1} k {\binom{- k + 2 m - 1}{m - 1}}}{m}&\text{if n=0,m>0} ,\ \\1&\text{if n=0,m=0} ,\ \\\frac{\left(-1\right)^{n + 1} k {\binom{k - m}{m}} {\binom{- k + m - 2 n - 1}{n - 1}}}{n} \end{cases} $$