Generating function
$$U_{1092}(x, y) = \frac{\left(y + 1\right)^{3} \left(- 2 x - \sqrt{1 - 4 x} + 1\right)^{3}}{8 x^{6}}$$
Explicit formula
$$T_{1092}(n, m, k) = \frac{3 k {\binom{3 k}{m}} {\binom{6 k + 2 n}{n}}}{3 k + n}$$
Data table
1 3 3 1 0 0 0
6 18 18 6 0 0 0
27 81 81 27 0 0 0
11 33 33 11 0 0 0
429 1287 1287 429 0 0 0
1638 4914 4914 1638 0 0 0
6188 18564 18564 6188 0 0 0
Export
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