$$U_{346}(x, y) = \frac{\left(- 2 x - \sqrt{1 - 4 x} + 1\right) \left(- 2 y - \sqrt{1 - 4 y} + 1\right)}{4 x^{2} y^{2}}$$

$$T_{346}(n, m, k) = \frac{k^{2} {\binom{2 k + 2 m}{m}} {\binom{2 k + 2 n}{n}}}{\left(k + m\right) \left(k + n\right)}$$