Generating function
$$U_{1102}(x, y) = \frac{x}{\left(1 - y\right)^{3}} + 1$$
Explicit formula
$$T_{1102}(n, m, k) = {\binom{k}{n}} {\binom{m + 3 n - 1}{m}}$$
Data table
1 0 0 0 0 0 0
1 3 6 1 15 21 28
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
Export
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