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arXiv · 2012.04523

Congruences concerning generalized central trinomial coefficients

Jia-Yu Chen·Chen Wang
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Abstract

For any $n\in\mathbb{N}=\{0,1,2,\ldots\}$ and $b,c\in\mathbb{Z}$, the generalized central trinomial coefficient $T_n(b,c)$ denotes the coefficient of $x^n$ in the expansion of $(x^2+bx+c)^n$. Let $p$ be an odd prime. In this paper, we determine the summation $\sum_{k=0}^{p-1}T_k(b,c)^2/m^k$ modulo $p^2$ for integers $m$ with certain restrictions. As applications, we confirm some conjectural congruences of Sun [Sci. China Math. 57 (2014), 1375--1400].

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Jia-Yu Chen, Chen Wang. 2020-12-08. Congruences concerning generalized central trinomial coefficients. https://arxiv.org/abs/2012.04523

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