$$U_{1308}(x, y) = \frac{128 y^{9} \left(- \frac{x \left(1 - \sqrt{1 - 4 y}\right)^{3}}{4 y^{3}} - \sqrt{- \frac{x \left(1 - \sqrt{1 - 4 y}\right)^{3}}{2 y^{3}} + 1} + 1\right)^{2}}{x^{4} \left(1 - \sqrt{1 - 4 y}\right)^{9}}$$

$$T_{1308}(n, m, k) = \frac{6 k \left(k + n\right) {\binom{4 k + 2 n}{n}} {\binom{3 k + 2 m + 3 n - 1}{m}}}{\left(2 k + n\right) \left(3 k + m + 3 n\right)}$$