$$U_{1053}(x, y) = \frac{\left(1 - \sqrt{1 - 4 x}\right) \left(1 - \sqrt{1 - 4 y}\right)^{2}}{8 x y^{2}}$$

$$T_{1053}(n, m, k) = \frac{2 k^{2} {\binom{k + 2 n - 1}{n}} {\binom{2 k + 2 m - 1}{m}}}{\left(k + n\right) \left(2 k + m\right)}$$