Extremal $Q$-index problem in outerplanar graphs
Combinatorics
2026-01-06 v1
Abstract
Outerplanar Tur\'an problem has received considerable attention recently. We study the spectral version via -index. We determine the unique graph that maximizes the -index among all -vertex connected outerplanar graphs which are respectively forbidden to contain: (i) a fixed cycle; and (ii) the disjoint union of paths of a given order.
Keywords
Cite
@article{arxiv.2601.01164,
title = {Extremal $Q$-index problem in outerplanar graphs},
author = {Jin Cai and Leyou Xu and Bo Zhou},
journal= {arXiv preprint arXiv:2601.01164},
year = {2026}
}