PreprintCC BY-NC-SA 4.0arXiv
Bounds on the number of squares in recurrence sequences: y0=b2 (II)
Abstract
For binary recurrence sequences, ( yk )k ∈ bbZ, arising from the solutions of generalised Pell equations, X2−dY2=c, where y0 is any positive square and c=−2ℓpm for an odd prime p and non-negative integers ℓ and m, we show that there are at most $4$ distinct squares with yk sufficiently large. From this result, we also show that there are at most $7$ distinct squares when y0=1,22,…,72, or once d exceeds an explicit lower bound, without any conditions on the size of such squares.
Versions
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BibTeX
@misc{voutier2026bounds,
title = {{Bounds on the number of squares in recurrence sequences: $y_0=b^2$ (II)}},
author = {Paul M Voutier},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.35158},
eprint = {2610.35158},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.35158},
note = {CC BY-NC-SA 4.0},
}
RIS
TY - UNPB
TI - Bounds on the number of squares in recurrence sequences: y_0=b^2 (II)
AU - Paul M Voutier
PY - 2026
DA - 2026/10/26
PB - arXiv
DO - 10.48550/arxiv.2610.35158
UR - https://arxiv.org/abs/2610.35158
AB - For binary recurrence sequences, ( y_k )_k ∈ bbZ, arising from the solutions of generalised Pell equations, X^2−dY^2=c, where y_0 is any positive square and c=−2^ℓp^m for an odd prime p and non-negative integers ℓ and m, we show that there are at most $4$ distinct squares with y_k sufficiently large. From this result, we also show that there are at most $7$ distinct squares when y_0=1,2^2,…,7^2, or once d exceeds an explicit lower bound, without any conditions on the size of such squares.
ER -