$$U_{60}(x, y) = \frac{- 2 x - \sqrt{- 4 x^{2} y - 4 x + 1} + 1}{2 x^{2}}$$

$$T_{60}(n, m, k) = \frac{k {\binom{k + n}{m}} {\binom{2 k - 2 m + 2 n}{n}}}{k + n}$$