Generating function
$$U_{1056}(x, y) = 15661$$ $$U_{1056}(x, y) = \frac{\left(1 - \sqrt{1 - 4 x}\right) \left(- 2 y - \sqrt{1 - 4 y} + 1\right)^{2}}{8 x y^{4}}$$
Explicit formula
$$T_{1056}(n, m, k) = \begin{cases}\frac{2 k^{2} {\binom{4 k + 2 m}{m}} {\binom{k + 2 n - 1}{n}}}{\left(k + n\right) \left(2 k + m\right)},\ \\1&\text{if n=0,m=0} \end{cases} $$
Data table
1 4 14 48 165 572 2002
1 4 14 48 165 572 2002
2 8 28 96 33 1144 4004
5 2 7 24 825 286 1001
14 56 196 672 231 8008 28028
42 168 588 2016 693 24024 84084
132 528 1848 6336 2178 75504 264264
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