{ "id": "2407.12868", "version": "v1", "published": "2024-07-13T16:06:21.000Z", "updated": "2024-07-13T16:06:21.000Z", "title": "Sum of Consecutive Terms of Pell and Related Sequences", "authors": [ "Navvye Anand", "Amit Kumar Basistha", "Kenny B. Davenport", "Alexander Gong", "Steven J. Miller", "Alexander Zhu" ], "comment": "33 Pages. Comments welcome!", "categories": [ "math.NT", "math.CO" ], "abstract": "We study new identities related to the sums of adjacent terms in the Pell sequence, defined by $P_{n} := 2P_{n-1}+P_{n-2}$ for $ n\\geq 2$ and $P_{0}=0, P_{1}=1$, and generalize these identities for many similar sequences. We prove that the sum of $N>1$ consecutive Pell numbers is a fixed integer multiple of another Pell number if and only if $4\\mid N$. We consider the generalized Pell $(k,i)$-numbers defined by $p(n) :=\\ 2p(n-1)+p(n-k-1) $ for $n\\geq k+1$, with $p(0)=p(1)=\\cdots =p(i)=0$ and $p(i+1)=\\cdots = p(k)=1$ for $0\\leq i\\leq k-1$, and prove that the sum of $N=2k+2$ consecutive terms is a fixed integer multiple of another term in the sequence. We also prove that for the generalized Pell $(k,k-1)$-numbers such a relation does not exist when $N$ and $k$ are odd. We give analogous results for the Fibonacci and other related second-order recursive sequences.", "revisions": [ { "version": "v1", "updated": "2024-07-13T16:06:21.000Z" } ], "analyses": { "subjects": [ "11Bxx", "11B37", "11B39", "11B50" ], "keywords": [ "consecutive terms", "related sequences", "fixed integer multiple", "generalized pell", "identities" ], "note": { "typesetting": "TeX", "pages": 33, "language": "en", "license": "arXiv", "status": "editable" } } }