$$U_{1334}(x, y) = \frac{x}{\left(1 - y\right)^{2}} + \frac{1}{\left(1 - y\right)^{4}}$$

$$T_{1334}(n, m, k) = {\binom{k}{n}} {\binom{4 k + m - 2 n - 1}{m}}$$