Pyramid #222
Generating function
$$U_{222}(x, y) = \frac{- 2 x - \sqrt{1 - 4 x} + 1}{2 x^{2} \left(1 - y\right)}$$
Explicit formula
$$T_{222}(n, m, k) = \frac{k {\binom{2 k + 2 n}{n}} {\binom{k + m - 1}{m}}}{k + n}$$
Data table
1 1 1 1 1 1 1
2 2 2 2 2 2 2
5 5 5 5 5 5 5
14 14 14 14 14 14 14
42 42 42 42 42 42 42
132 132 132 132 132 132 132
429 429 429 429 429 429 429
Export
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