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arXiv · 1410.6234

On $k$-Fibonacci sums by matrix methods

Gamaliel Cerda
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Abstract

In this paper, some $k$-Fibonacci and $k$-Lucas with arithmetic indexes sums are derived by using the matrices $R_{a}=\left[ \begin{array}{lr} L_{k,a} & -(-1)^{a} \\ 1 & 0 \end{array}\right]$ and $S_{a}=\frac{1}{2}\left[ \begin{array}{lr} L_{k,a} & Δ_{a} \\ 1 & L_{k,a} \end{array}\right]$, where $Δ_{a}=L_{k,a}^{2}-4(-1)^{a}$. The most notable side of this paper is our proof method, since all the identities used in the proofs of main theorems are proved previously by using the matrices $R_{a}$ and $S_{a}$, with $a$ an natural number. Although the identities we proved are known, our proofs are not encountered in the $k$-Fibonacci and $k$-Lucas numbers literature.

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Gamaliel Cerda. 2014-10-23. On $k$-Fibonacci sums by matrix methods. https://arxiv.org/abs/1410.6234

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