$$U_{593}(x, y) = \frac{- \sqrt{4 y + 1} - 1}{\frac{x \left(\sqrt{4 y + 1} + 1\right)^{3}}{4} - 2}$$

$$T_{593}(n, m, k) = \begin{cases}{\binom{k + n - 1}{n}}&\text{if m==0} ,\ \\\frac{\left(-1\right)^{m - 1} \left(k + 3 n\right) {\binom{k + n - 1}{n}} {\binom{- k + 2 m - 3 n - 1}{m - 1}}}{m}&\text{if m>0} \end{cases} $$