$$U_{152}(x, y) = \frac{- 2 x y - \sqrt{4 x y^{2} + 4 x y + 1} - 1}{2 x - 2}$$

$$T_{152}(n, m, k) = \begin{cases}1&\text{if n=0, m=0} ,\ \\0&\text{if n=0} ,\ \\\frac{\left(-1\right)^{n - 1} k {\binom{2 n}{- k + n}}}{n}&\text{if n>0 and n+k=m} ,\ \\\frac{k {\binom{2 n}{m}} {\binom{k - m + n}{n}}}{k - m + n} \end{cases} $$