Zeckendorf family identities generalized
Abstract: Philip Matchett Wood and Doron Zeilberger have constructed identities for the Fibonacci numbers $f_n$ of the form $1f_n = f_n$ for all $n \geq 1$; $2f_n = f_{n-2} + f_{n+1}$ for all $n \geq 3$; $3f_n = f_{n-2} + f_{n+2}$ for all $n \geq 3$; $4f_n = f_{n-2} + f_{n} + f_{n+2}$ for all $n \geq 3$; ...; the general identity in this family has the form $kf_n = \sum_{s \in S_k} f_{n+s}$ (for all sufficiently high $n$), where $S_k$ is a finite set of integers that depends only on $k$ and contains no two consecutive integers. These identities are generalized, replacing the left-hand side $kf_n$ by arbitrary sums of the form $f_{n+a_1} + f_{n+a_2} + \cdots + f_{n+a_p}$ for arbitrary integers $a_1, a_2, \ldots, a_p$. The resulting theorem is proved using the connection between the Fibonacci numbers and the golden ratio.
Paper Prompts
Sign up for free to create and run prompts on this paper using GPT-5.
Top Community Prompts
Collections
Sign up for free to add this paper to one or more collections.