Generating function
$$U_{1052}(x, y) = \frac{\left(1 - \sqrt{1 - 4 x}\right) \left(y + 1\right)^{3}}{2 x}$$
Explicit formula
$$T_{1052}(n, m, k) = \frac{k {\binom{3 k}{m}} {\binom{k + 2 n - 1}{n}}}{k + n}$$
Data table
1 3 3 1 0 0 0
1 3 3 1 0 0 0
2 6 6 2 0 0 0
5 15 15 5 0 0 0
14 42 42 14 0 0 0
42 126 126 42 0 0 0
132 396 396 132 0 0 0
Export
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