$$U_{751}(x, y) = \frac{\left(\frac{x \left(- 2 y - \sqrt{1 - 4 y} + 1\right)}{2 y^{2}} + 1\right)^{2} \left(- 2 y - \sqrt{1 - 4 y} + 1\right)}{2 y^{2}}$$

$$T_{751}(n, m, k) = \frac{\left(k + n\right) {\binom{2 k}{n}} {\binom{2 k + 2 m + 2 n}{m}}}{k + m + n}$$