Word-Representability of Split Graphs with Independent Set of Size 4

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Roy, Suchanda, Hariharasubramanian, Ramesh
Natura: Preprint
Pubblicazione: 2025
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866918088938618880
author Roy, Suchanda
Hariharasubramanian, Ramesh
author_facet Roy, Suchanda
Hariharasubramanian, Ramesh
contents A pair of letters $x$ and $y$ are said to alternate in a word $w$ if, after removing all letters except for the copies of $x$ and $y$ from $w$, the resulting word is of the form $xyxy\ldots$ (of even or odd length) or $yxyx\ldots$ (of even or odd length). A graph $G = (V (G), E(G))$ is word-representable if there exists a word $w$ over the alphabet $V(G)$, such that any two distinct vertices $x, y \in V (G)$ are adjacent in $G$ (i.e., $xy \in E(G)$) if and only if the letters $x$ and $y$ alternate in $w$. A split graph is a graph in which the vertices can be partitioned into a clique and an independent set. Word-representability of split graphs has been studied in a series of papers [2, 5, 7, 9] in the literature. In this work, we give a minimal forbidden induced subgraph characterization of word-representable split graphs with an independent set of size 4, which is an open problem posed by Kitaev and Pyatkin in [9]
format Preprint
id arxiv_https___arxiv_org_abs_2507_08483
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Word-Representability of Split Graphs with Independent Set of Size 4
Roy, Suchanda
Hariharasubramanian, Ramesh
Combinatorics
Discrete Mathematics
A pair of letters $x$ and $y$ are said to alternate in a word $w$ if, after removing all letters except for the copies of $x$ and $y$ from $w$, the resulting word is of the form $xyxy\ldots$ (of even or odd length) or $yxyx\ldots$ (of even or odd length). A graph $G = (V (G), E(G))$ is word-representable if there exists a word $w$ over the alphabet $V(G)$, such that any two distinct vertices $x, y \in V (G)$ are adjacent in $G$ (i.e., $xy \in E(G)$) if and only if the letters $x$ and $y$ alternate in $w$. A split graph is a graph in which the vertices can be partitioned into a clique and an independent set. Word-representability of split graphs has been studied in a series of papers [2, 5, 7, 9] in the literature. In this work, we give a minimal forbidden induced subgraph characterization of word-representable split graphs with an independent set of size 4, which is an open problem posed by Kitaev and Pyatkin in [9]
title Word-Representability of Split Graphs with Independent Set of Size 4
topic Combinatorics
Discrete Mathematics
url https://arxiv.org/abs/2507.08483