$$U_{1274}(x, y) = \frac{y^{2} \left(1 - \sqrt{- \frac{x \left(1 - \sqrt{1 - 4 y}\right)^{2}}{y^{2}} + 1}\right)^{2}}{x^{2} \left(1 - \sqrt{1 - 4 y}\right)^{2}}$$

$$T_{1274}(n, m, k) = \frac{4 k \left(k + n\right) {\binom{2 k + 2 n - 1}{n}} {\binom{2 k + 2 m + 2 n - 1}{m}}}{\left(2 k + n\right) \left(2 k + m + 2 n\right)}$$