PreprintCC BY 4.0arXiv
The Distance Laplacian and Distance Signless Laplacian Spectra of 𝒞-Graphs
Abstract
Mandal and Mehatari (\emph{Comp.\ Appl.\ Math.}, 2025) introduced the class 𝒞 of cographs generated by a finite creation sequence (α1,…,αm) of natural numbers, and derived the inertia, an extended eigenvalue-free interval, and the exact characteristic polynomial for the \emph{adjacency} matrix of such graphs. In this note we develop the parallel theory for the \emph{distance Laplacian} matrix DL(G) and \emph{distance signless Laplacian} matrix DQ(G). It is shown that (0,αmin) ∪ (n−αmin, n), (0,n) ∪ (n, n+αmin) ∪ (2n−αmin, 2n), (2Trmin, μmax(DQ(G))) are the eigenvalue-free intervals of the Laplacian, distance Laplacian, and distance signless Laplacian matrices respectively for the said class of graphs.
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BibTeX
@misc{mandal2026distance,
title = {{The Distance Laplacian and Distance Signless Laplacian Spectra of $\mathcalC$-Graphs}},
author = {Santanu Mandal and Pallabi Manna},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.08599},
eprint = {2610.08599},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.08599},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - The Distance Laplacian and Distance Signless Laplacian Spectra of 𝒞-Graphs
AU - Santanu Mandal
AU - Pallabi Manna
PY - 2026
DA - 2026/10/06
PB - arXiv
DO - 10.48550/arxiv.2610.08599
UR - https://arxiv.org/abs/2610.08599
AB - Mandal and Mehatari (\emph{Comp.\ Appl.\ Math.}, 2025) introduced the class 𝒞 of cographs generated by a finite creation sequence (α_1,…,α_m) of natural numbers, and derived the inertia, an extended eigenvalue-free interval, and the exact characteristic polynomial for the \emph{adjacency} matrix of such graphs. In this note we develop the parallel theory for the \emph{distance Laplacian} matrix D^L(G) and \emph{distance signless Laplacian} matrix D^Q(G). It is shown that (0,α_min) ∪ (n−α_min, n), (0,n) ∪ (n, n+α_min) ∪ (2n−α_min, 2n), (2Tr_min, μ_max(D^Q(G))) are the eigenvalue-free intervals of the Laplacian, distance Laplacian, and distance signless Laplacian matrices respectively for the said class of graphs.
ER -