Pyramid #827
Generating function
$$U_{827}(x, y) = \frac{x y - 1}{x y + x - 1}$$
Explicit formula
$$T_{827}(n, m, k) = {\binom{n - 1}{m}} {\binom{k - m + n - 1}{- m + n}}$$
Data table
1 0 0 0 0 0 0
1 0 0 0 0 0 0
1 1 0 0 0 0 0
1 2 1 0 0 0 0
1 3 3 1 0 0 0
1 4 6 4 1 0 0
1 5 1 1 5 1 0
Export
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