On the $e$-Positivity of $(claw, 2K_2)$-Free Graphs
Motivated by Stanley and Stembridge's conjecture about the $e$-positivity of claw-free incomparability graphs, Hamel and her collaborators studied the $e$-positivity of $(claw, H)$-free graphs, where $H$ is a four-vertex graph. In this paper we establish the $e$-positivity of generalized pyrami...
Gespeichert in:
| Veröffentlicht in: | The Electronic journal of combinatorics 2021-06, Vol.28 (2) |
|---|---|
| Hauptverfasser: | , |
| Format: | Artikel |
| Sprache: | eng |
| Online-Zugang: | Volltext |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| container_end_page | |
|---|---|
| container_issue | 2 |
| container_start_page | |
| container_title | The Electronic journal of combinatorics |
| container_volume | 28 |
| creator | Li, Grace M. X. Yang, Arthur L. B. |
| description | Motivated by Stanley and Stembridge's conjecture about the $e$-positivity of claw-free incomparability graphs, Hamel and her collaborators studied the $e$-positivity of $(claw, H)$-free graphs, where $H$ is a four-vertex graph. In this paper we establish the $e$-positivity of generalized pyramid graphs and $2K_2$-free unit interval graphs, which are two important families of $(claw, 2K_2)$-free graphs. Hence we affirmatively solve one problem proposed by Hamel, Hoáng and Tuero, and another problem considered by Foley, Hoáng and Merkel. |
| doi_str_mv | 10.37236/9910 |
| format | Article |
| fullrecord | <record><control><sourceid>crossref</sourceid><recordid>TN_cdi_crossref_primary_10_37236_9910</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><sourcerecordid>10_37236_9910</sourcerecordid><originalsourceid>FETCH-LOGICAL-c151t-ad27ed30fe35a8120b38a89b8d4ba71d346620c36f943a4d5ea078cd863637563</originalsourceid><addsrcrecordid>eNpNj8tKAzEUQIMoWGv_IYsRFIwmuZPXUkpbxUJd6DrcyYOOVKckg9K_Fx8LV-esDhxCZoLfgJGgb50T_IhMBDeGWSf18T8_JWe1vnIupHNqQmDzTsdtok1q2NNQ-7H_6McDHTJtLsMOP6-pfPTyqmHLkhJdFdxv6zk5ybirafbHKXlZLp7n92y9WT3M79YsCCVGhlGaFIHnBAqtkLwDi9Z1NrYdGhGh1VryADq7FrCNKiE3NkSrQYNRGqbk4rcbylBrSdnvS_-G5eAF9z-n_vsUvgDNw0ET</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype></control><display><type>article</type><title>On the $e$-Positivity of $(claw, 2K_2)$-Free Graphs</title><source>DOAJ Directory of Open Access Journals</source><source>EZB-FREE-00999 freely available EZB journals</source><creator>Li, Grace M. X. ; Yang, Arthur L. B.</creator><creatorcontrib>Li, Grace M. X. ; Yang, Arthur L. B.</creatorcontrib><description>Motivated by Stanley and Stembridge's conjecture about the $e$-positivity of claw-free incomparability graphs, Hamel and her collaborators studied the $e$-positivity of $(claw, H)$-free graphs, where $H$ is a four-vertex graph. In this paper we establish the $e$-positivity of generalized pyramid graphs and $2K_2$-free unit interval graphs, which are two important families of $(claw, 2K_2)$-free graphs. Hence we affirmatively solve one problem proposed by Hamel, Hoáng and Tuero, and another problem considered by Foley, Hoáng and Merkel.</description><identifier>ISSN: 1077-8926</identifier><identifier>EISSN: 1077-8926</identifier><identifier>DOI: 10.37236/9910</identifier><language>eng</language><ispartof>The Electronic journal of combinatorics, 2021-06, Vol.28 (2)</ispartof><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c151t-ad27ed30fe35a8120b38a89b8d4ba71d346620c36f943a4d5ea078cd863637563</citedby></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><link.rule.ids>314,780,784,864,27924,27925</link.rule.ids></links><search><creatorcontrib>Li, Grace M. X.</creatorcontrib><creatorcontrib>Yang, Arthur L. B.</creatorcontrib><title>On the $e$-Positivity of $(claw, 2K_2)$-Free Graphs</title><title>The Electronic journal of combinatorics</title><description>Motivated by Stanley and Stembridge's conjecture about the $e$-positivity of claw-free incomparability graphs, Hamel and her collaborators studied the $e$-positivity of $(claw, H)$-free graphs, where $H$ is a four-vertex graph. In this paper we establish the $e$-positivity of generalized pyramid graphs and $2K_2$-free unit interval graphs, which are two important families of $(claw, 2K_2)$-free graphs. Hence we affirmatively solve one problem proposed by Hamel, Hoáng and Tuero, and another problem considered by Foley, Hoáng and Merkel.</description><issn>1077-8926</issn><issn>1077-8926</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2021</creationdate><recordtype>article</recordtype><recordid>eNpNj8tKAzEUQIMoWGv_IYsRFIwmuZPXUkpbxUJd6DrcyYOOVKckg9K_Fx8LV-esDhxCZoLfgJGgb50T_IhMBDeGWSf18T8_JWe1vnIupHNqQmDzTsdtok1q2NNQ-7H_6McDHTJtLsMOP6-pfPTyqmHLkhJdFdxv6zk5ybirafbHKXlZLp7n92y9WT3M79YsCCVGhlGaFIHnBAqtkLwDi9Z1NrYdGhGh1VryADq7FrCNKiE3NkSrQYNRGqbk4rcbylBrSdnvS_-G5eAF9z-n_vsUvgDNw0ET</recordid><startdate>20210618</startdate><enddate>20210618</enddate><creator>Li, Grace M. X.</creator><creator>Yang, Arthur L. B.</creator><scope>AAYXX</scope><scope>CITATION</scope></search><sort><creationdate>20210618</creationdate><title>On the $e$-Positivity of $(claw, 2K_2)$-Free Graphs</title><author>Li, Grace M. X. ; Yang, Arthur L. B.</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c151t-ad27ed30fe35a8120b38a89b8d4ba71d346620c36f943a4d5ea078cd863637563</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2021</creationdate><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Li, Grace M. X.</creatorcontrib><creatorcontrib>Yang, Arthur L. B.</creatorcontrib><collection>CrossRef</collection><jtitle>The Electronic journal of combinatorics</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Li, Grace M. X.</au><au>Yang, Arthur L. B.</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>On the $e$-Positivity of $(claw, 2K_2)$-Free Graphs</atitle><jtitle>The Electronic journal of combinatorics</jtitle><date>2021-06-18</date><risdate>2021</risdate><volume>28</volume><issue>2</issue><issn>1077-8926</issn><eissn>1077-8926</eissn><abstract>Motivated by Stanley and Stembridge's conjecture about the $e$-positivity of claw-free incomparability graphs, Hamel and her collaborators studied the $e$-positivity of $(claw, H)$-free graphs, where $H$ is a four-vertex graph. In this paper we establish the $e$-positivity of generalized pyramid graphs and $2K_2$-free unit interval graphs, which are two important families of $(claw, 2K_2)$-free graphs. Hence we affirmatively solve one problem proposed by Hamel, Hoáng and Tuero, and another problem considered by Foley, Hoáng and Merkel.</abstract><doi>10.37236/9910</doi><oa>free_for_read</oa></addata></record> |
| fulltext | fulltext |
| identifier | ISSN: 1077-8926 |
| ispartof | The Electronic journal of combinatorics, 2021-06, Vol.28 (2) |
| issn | 1077-8926 1077-8926 |
| language | eng |
| recordid | cdi_crossref_primary_10_37236_9910 |
| source | DOAJ Directory of Open Access Journals; EZB-FREE-00999 freely available EZB journals |
| title | On the $e$-Positivity of $(claw, 2K_2)$-Free Graphs |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2024-12-21T09%3A05%3A34IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-crossref&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=On%20the%20$e$-Positivity%20of%20$(claw,%202K_2)$-Free%20Graphs&rft.jtitle=The%20Electronic%20journal%20of%20combinatorics&rft.au=Li,%20Grace%20M.%20X.&rft.date=2021-06-18&rft.volume=28&rft.issue=2&rft.issn=1077-8926&rft.eissn=1077-8926&rft_id=info:doi/10.37236/9910&rft_dat=%3Ccrossref%3E10_37236_9910%3C/crossref%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_id=info:pmid/&rfr_iscdi=true |