On Longest Cycles in Essentially 4-Connected Planar Graphs

A planar 3-connected graph G is essentially 4-connected if, for any 3-separator S of G, one component of the graph obtained from G by removing S is a single vertex. Jackson and Wormald proved that an essentially 4-connected planar graph on n vertices contains a cycle C such that . For a cubic essent...

Full description

Bibliographic Details
Main Authors: Fabrici Igor, Harant Jochen, Jendroľ Stanislav
Format: Article
Language:English
Published: University of Zielona Góra 2016-08-01
Series:Discussiones Mathematicae Graph Theory
Subjects:
Online Access:https://doi.org/10.7151/dmgt.1875
_version_ 1797717989836980224
author Fabrici Igor
Harant Jochen
Jendroľ Stanislav
author_facet Fabrici Igor
Harant Jochen
Jendroľ Stanislav
author_sort Fabrici Igor
collection DOAJ
description A planar 3-connected graph G is essentially 4-connected if, for any 3-separator S of G, one component of the graph obtained from G by removing S is a single vertex. Jackson and Wormald proved that an essentially 4-connected planar graph on n vertices contains a cycle C such that . For a cubic essentially 4-connected planar graph G, Grünbaum with Malkevitch, and Zhang showed that G has a cycle on at least ¾ n vertices. In the present paper the result of Jackson and Wormald is improved. Moreover, new lower bounds on the length of a longest cycle of G are presented if G is an essentially 4-connected planar graph of maximum degree 4 or G is an essentially 4-connected maximal planar graph.
first_indexed 2024-03-12T08:44:28Z
format Article
id doaj.art-00c53a1b75f6495ca1f93b22bcedef76
institution Directory Open Access Journal
issn 2083-5892
language English
last_indexed 2024-03-12T08:44:28Z
publishDate 2016-08-01
publisher University of Zielona Góra
record_format Article
series Discussiones Mathematicae Graph Theory
spelling doaj.art-00c53a1b75f6495ca1f93b22bcedef762023-09-02T16:29:58ZengUniversity of Zielona GóraDiscussiones Mathematicae Graph Theory2083-58922016-08-0136356557510.7151/dmgt.1875dmgt.1875On Longest Cycles in Essentially 4-Connected Planar GraphsFabrici Igor0Harant Jochen1Jendroľ Stanislav2Institute of Mathematics P.J. Šafárik University in Košice, SlovakiaInstitute of Mathematics Ilmenau University of Technology, GermanyInstitute of Mathematics P.J. Šafárik University in Košice, SlovakiaA planar 3-connected graph G is essentially 4-connected if, for any 3-separator S of G, one component of the graph obtained from G by removing S is a single vertex. Jackson and Wormald proved that an essentially 4-connected planar graph on n vertices contains a cycle C such that . For a cubic essentially 4-connected planar graph G, Grünbaum with Malkevitch, and Zhang showed that G has a cycle on at least ¾ n vertices. In the present paper the result of Jackson and Wormald is improved. Moreover, new lower bounds on the length of a longest cycle of G are presented if G is an essentially 4-connected planar graph of maximum degree 4 or G is an essentially 4-connected maximal planar graph.https://doi.org/10.7151/dmgt.1875planar graphlongest cycle
spellingShingle Fabrici Igor
Harant Jochen
Jendroľ Stanislav
On Longest Cycles in Essentially 4-Connected Planar Graphs
Discussiones Mathematicae Graph Theory
planar graph
longest cycle
title On Longest Cycles in Essentially 4-Connected Planar Graphs
title_full On Longest Cycles in Essentially 4-Connected Planar Graphs
title_fullStr On Longest Cycles in Essentially 4-Connected Planar Graphs
title_full_unstemmed On Longest Cycles in Essentially 4-Connected Planar Graphs
title_short On Longest Cycles in Essentially 4-Connected Planar Graphs
title_sort on longest cycles in essentially 4 connected planar graphs
topic planar graph
longest cycle
url https://doi.org/10.7151/dmgt.1875
work_keys_str_mv AT fabriciigor onlongestcyclesinessentially4connectedplanargraphs
AT harantjochen onlongestcyclesinessentially4connectedplanargraphs
AT jendrolstanislav onlongestcyclesinessentially4connectedplanargraphs