A new $q$-analogue of the binomial identity $\sum_{k}(-1)^k{2n\choose n+3k}=2\cdot 3^{n-1}$

Document Type : Research Paper

Authors

Department of Mathematics, Wenzhou University, Wenzhou, PR China

Abstract

In this paper, we establish a new $q$-analogue of the binomial identity:
\begin{align*}
&\sum_{k}(-1)^k{2n\choose n+3k}=
\begin{cases}
1,&\text{if $n=0$,}\\[5pt]
2\cdot3^{n-1},&\text{if $n\ge 1$.}
\end{cases}
\end{align*}
Our proof relies on a weight-preserving and sign-reversing involution due to Guo and Zhang.

Keywords

Main Subjects


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  • Receive Date: 29 September 2022
  • Revise Date: 01 February 2023
  • Accept Date: 05 February 2023
  • Published Online: 01 June 2024