Generating function
$$U_{1172}(x, y) = \frac{\left(1 - y\right)^{6} \left(1 - \sqrt{- \frac{4 x}{\left(1 - y\right)^{2}} + 1}\right)^{3}}{8 x^{3}}$$
Explicit formula
$$T_{1172}(n, m, k) = \frac{3 k {\binom{3 k + 2 n - 1}{n}} {\binom{m + 2 n - 1}{m}}}{3 k + n}$$
Data table
1 0 0 0 0 0 0
3 6 9 12 15 18 21
9 36 9 18 315 504 756
28 168 588 1568 3528 7056 12936
9 72 324 108 297 7128 15444
297 297 16335 6534 212355 594594 1486485
1001 12012 78078 364364 1366365 4372368 12388376
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