Generating function
$$U_{1471}(x, y) = \frac{2 \sqrt{3} \sin{\left(\frac{\operatorname{asin}{\left(\frac{3 \sqrt{3} \sqrt{\frac{x}{\left(1 - y\right)^{2}}}}{2} \right)}}{3} \right)}}{3 \sqrt{x}}$$
Explicit formula
$$T_{1471}(n, m, k) = \frac{k {\binom{k + 3 n - 1}{n}} {\binom{k + m + 2 n - 1}{m}}}{k + 2 n}$$
Data table
1 1 1 1 1 1 1
1 3 6 1 15 21 28
3 15 45 105 21 378 63
12 84 336 1008 252 5544 11088
55 495 2475 9075 27225 70785 165165
273 3003 18018 78078 273273 819819 2186184
1428 18564 129948 64974 259896 8836464 26509392
Export
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