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A curious polynomial interpolation of Carlitz-Riordans $q$-ballot numbers

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 Added by Jiang Zeng
 Publication date 2013
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and research's language is English




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We study a polynomial sequence $C_n(x|q)$ defined as a solution of a $q$-difference equation. This sequence, evaluated at $q$-integers, interpolates Carlitz-Riordans $q$-ballot numbers. In the basis given by some kind of $q$-binomial coefficients, the coefficients are again some $q$-ballot numbers. We obtain in a combinatorial way another curious recurrence relation for these polynomials.



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