Generating function
$$U_{1340}(x, y) = \frac{2 \sqrt{3} \sin{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{x} \left(y + 1\right)^{3}}{2} \right)}}{3} \right)}}{3 \sqrt{x}}$$
Explicit formula
$$T_{1340}(n, m, k) = \frac{k {\binom{k + 3 n}{n}} {\binom{3 k + 6 n}{m}}}{k + 3 n}$$
Data table
1 3 3 1 0 0 0
1 9 36 84 126 126 84
3 45 315 1365 4095 9009 15015
12 252 252 1596 7182 244188 651168
55 1485 19305 160875 96525 444015 1628055
273 9009 144144 1489488 1117116 64792728 302366064
1428 55692 1058148 13050492 117454428 822180996 4659025644
Export
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