Generating function
$$U_{1390}(x, y) = \frac{y}{1 - x} + 1$$
Explicit formula
$$T_{1390}(n, m, k) = {\binom{k}{m}} {\binom{m + n - 1}{n}}$$
Data table
1 1 0 0 0 0 0
0 1 0 0 0 0 0
0 1 0 0 0 0 0
0 1 0 0 0 0 0
0 1 0 0 0 0 0
0 1 0 0 0 0 0
0 1 0 0 0 0 0
Export
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