Pyramid #312
Generating function
$$U_{312}(x, y) = \frac{- x y^{2} + 2 x y - x - 1}{y - 1}$$
Explicit formula
$$T_{312}(n, m, k) = {\binom{k}{n}} {\binom{k + m - 2 n - 1}{m}}$$
Data table
1 1 1 1 1 1 1
1 -1 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 0 0 0 0 0
0 0 0 0 0 0 0
Export
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