Generating function
$$U_{1137}(x, y) = \frac{1}{\left(- \frac{x}{\left(1 - y\right)^{3}} + 1\right)^{2}}$$
Explicit formula
$$T_{1137}(n, m, k) = {\binom{2 k + n - 1}{n}} {\binom{m + 3 n - 1}{m}}$$
Data table
1 0 0 0 0 0 0
2 6 12 2 3 42 56
3 18 63 168 378 756 1386
4 36 18 66 198 5148 12012
5 6 39 182 6825 2184 6188
6 9 72 408 1836 69768 23256
7 126 1197 798 41895 184338 706629
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