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arXiv · 2501.03438

Fibonacci Numbers as Sums of Consecutive Terms in $k$-Generalized Fibonacci Sequence

Roberto Alvarenga·Ana Paula Chaves·Maria Eduarda Ramos·Matheus Silva·Marcos Sosa
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Abstract

Let (F_n^{(k)})_{n\geq -(k-2)} be the k-generalized Fibonacci sequence, defined as the linear recurrence sequence whose first k terms are \(0, 0, \ldots, 0, 1\), and whose subsequent terms are determined by the sum of the preceding k terms. This article is devoted to investigating when the sum of consecutive numbers in the k-generalized Fibonacci sequence belongs to the Fibonacci sequence. Namely, given d,k \in \N, with k \geq 3, our main theorem states that there are at most finitely many n \in \N such that F_n^{(k)} + \cdots + F_{n+d}^{(k)} is a Fibonacci number. In particular, the intersection between the Fibonacci sequence and the k-generalized Fibonacci sequence is finite.

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Roberto Alvarenga, Ana Paula Chaves, Maria Eduarda Ramos, Matheus Silva, Marcos Sosa. 2025-01-06. Fibonacci Numbers as Sums of Consecutive Terms in $k$-Generalized Fibonacci Sequence. https://arxiv.org/abs/2501.03438

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