Generating function
$$U_{1124}(x, y) = \left(\frac{x \left(1 - \sqrt{1 - 4 y}\right)}{2 y} + 1\right)^{3}$$
Explicit formula
$$T_{1124}(n, m, k) = \begin{cases}1&\text{if n=0,m=0} ,\ \\\frac{n {\binom{3 k}{n}} {\binom{2 m + n - 1}{m}}}{m + n} \end{cases} $$
Data table
1 0 0 0 0 0 0
3 3 6 15 42 126 396
3 6 15 42 126 396 1287
1 3 9 28 9 297 1001
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
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