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Four transformations on the Catalan triangle

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 Added by Yidong Sun
 Publication date 2013
  fields
and research's language is English




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In this paper, we define four transformations on the classical Catalan triangle $mathcal{C}=(C_{n,k})_{ngeq kgeq 0}$ with $C_{n,k}=frac{k+1}{n+1}binom{2n-k}{n}$. The first three ones are based on the determinant and the forth is utilizing the permanent of a square matrix. It not only produces many known and new identities involving Catalan numbers, but also provides a new viewpoint on combinatorial triangles.



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