Generating function
$$U_{1009}(x, y) = \frac{\left(x + 1\right)^{2}}{\left(1 - y\right)^{2}}$$
Explicit formula
$$T_{1009}(n, m, k) = {\binom{2 k}{n}} {\binom{2 k + m - 1}{m}}$$
Data table
1 2 3 4 5 6 7
2 4 6 8 1 12 14
1 2 3 4 5 6 7
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
0 0 0 0 0 0 0
Export
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