Generating function
$$U_{1467}(x, y) = \frac{2 \sqrt{3} \sin{\left(\frac{\arcsin{\left(\frac{3 \sqrt{3} \sqrt{x \left(y + 1\right)^{3}}}{2} \right)}}{3} \right)}}{3 \sqrt{x \left(y + 1\right)}}$$
Explicit formula
$$T_{1467}(n, m, k) = \frac{k {\binom{k + 3 n}{m}} {\binom{k + 3 n - 1}{n}}}{k + 2 n}$$
Data table
1 1 0 0 0 0 0
1 4 6 4 1 0 0
3 21 63 105 105 63 21
12 12 54 144 252 3024 252
55 715 429 1573 39325 70785 9438
273 4368 3276 15288 49686 1192464 2186184
1428 27132 244188 1383732 5534928 16604784 38744496
Export
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