Generating function
$$U_{1070}(x, y) = \frac{\left(1 - \sqrt{1 - 4 x}\right)^{3} \left(1 - \sqrt{1 - 4 y}\right)^{3}}{64 x^{3} y^{3}}$$
Explicit formula
$$T_{1070}(n, m, k) = \frac{9 k^{2} {\binom{3 k + 2 m - 1}{m}} {\binom{3 k + 2 n - 1}{n}}}{\left(3 k + m\right) \left(3 k + n\right)}$$
Data table
1 3 9 28 9 297 1001
3 9 27 84 27 891 3003
9 27 81 252 81 2673 9009
28 84 252 784 252 8316 28028
9 27 81 252 81 2673 9009
297 891 2673 8316 2673 88209 297297
1001 3003 9009 28028 9009 297297 1002001
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