$$U_{327}(x, y) = \frac{- x + \sqrt{x^{2} + 2 x + y \left(4 x^{2} + 4 x\right) + 1} - 1}{y \left(2 x^{2} + 2 x\right)}$$

$$T_{327}(n, m, k) = \begin{cases}\frac{\left(-1\right)^{n} k {\binom{k + 2 m - 1}{m}} {\binom{k + n - 1}{- m + n}}}{k + m},\ \\0&\text{if n<m} \end{cases} $$