$$U_{290}(x, y) = \frac{\sqrt{3} \sqrt{y} - \sqrt{- 16 x \sin^{2}{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)} + 3 y}}{4 x \sin{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{y}}{2} \right)}}{3} \right)}}$$

$$T_{290}(n, m, k) = \frac{k {\binom{k + 2 n}{n}} {\binom{k + 3 m + 2 n - 1}{m}}}{k + 2 m + 2 n}$$