Generating function
$$U_{1434}(x, y) = \frac{\left(y + 1\right)^{3}}{- x \left(y + 1\right)^{3} + 1}$$
Explicit formula
$$T_{1434}(n, m, k) = {\binom{3 k + 3 n}{m}} {\binom{k + n - 1}{n}}$$
Data table
1 3 3 1 0 0 0
1 6 15 2 15 6 1
1 9 36 84 126 126 84
1 12 66 22 495 792 924
1 15 105 455 1365 3003 5005
1 18 153 816 306 8568 18564
1 21 21 133 5985 20349 54264
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