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arXiv · 1505.00668

Congruences for Catalan-Larcombe-French numbers

Xiao-Juan Ji·Zhi-Hong Sun
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Abstract

Let $\{P_n\}$ be the Catalan-Larcombe-French numbers given by $P_0=1,\ P_1=8$ and $n^2P_n=8(3n^2-3n+1)P_{n-1}-128(n-1)^2P_{n-2}$ $(n\ge 2)$, and let $S_n=P_n/2^n$. In this paper we deduce congruences for $S_{mp^r}\pmod{p^{r+2}}$, $S_{mp^r-1}\pmod{p^r}$ and $S_{mp^r+1}\pmod{p^{2r}}$, where $p$ is an odd prime and $m,r$ are positive integers. We also prove that $S_{(p^2-1)/2}\equiv 0\pmod {p^2}$ for any prime $p\equiv 5,7\pmod 8$, and show that $\{S_m\}$ is log-convex.

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Xiao-Juan Ji, Zhi-Hong Sun. 2015-05-04. Congruences for Catalan-Larcombe-French numbers. https://arxiv.org/abs/1505.00668

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