Generating function
$$U_{1118}(x, y) = \left(x \left(y + 1\right) + 1\right)^{3}$$
Explicit formula
$$T_{1118}(n, m, k) = {\binom{3 k}{n}} {\binom{n}{m}}$$
Data table
1 0 0 0 0 0 0
3 3 0 0 0 0 0
3 6 3 0 0 0 0
1 3 3 1 0 0 0
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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