Pyramid #340
Generating function
$$U_{340}(x, y) = \frac{- y \left(2 x + 2\right) - \sqrt{y \left(4 x^{2} + 4 x\right) + 1} + 1}{2 y^{2} - 2 y}$$
Explicit formula
$$T_{340}(n, m, k) = \frac{k {\binom{2 k + 2 m}{n}} {\binom{k + m - n}{m}}}{k + m}$$
Data table
1 1 1 1 1 1 1
2 2 2 2 2 2 2
1 0 0 0 0 0 0
0 -2 0 0 0 0 0
0 -1 5 0 0 0 0
0 0 6 -14 0 0 0
0 0 2 -28 42 0 0
Export
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