The Nordhaus-Gaddum problem for the k-defective chromatic number of a P4-free graph

A graph is (m, k)-colourable if its vertices can be coloured with m colours such that the maximum degree of the subgraph induced on vertices receiving the same colour is at most k. The k-defective chromatic number Xk(G) of a graph G is the least positive integer m for which G is (m, k)-colourable. T...

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Main Authors: Achuthan, Nirmala, Achuthan, Narasimaha, Simanihuruk, M.
Format: Journal Article
Published: Centre for Discrete Mathematics and Computing 2011
Online Access:http://hdl.handle.net/20.500.11937/11944
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author Achuthan, Nirmala
Achuthan, Narasimaha
Simanihuruk, M.
author_facet Achuthan, Nirmala
Achuthan, Narasimaha
Simanihuruk, M.
author_sort Achuthan, Nirmala
building Curtin Institutional Repository
collection Online Access
description A graph is (m, k)-colourable if its vertices can be coloured with m colours such that the maximum degree of the subgraph induced on vertices receiving the same colour is at most k. The k-defective chromatic number Xk(G) of a graph G is the least positive integer m for which G is (m, k)-colourable. The Nordhaus-Gaddum problem is to find sharp bounds for Xk(G)+Xk(G) and Xk(G). Xk(G) over the set of all graphs of order p where G is the complement of the graph G. In this paper we obtain a sharp upper bound for Xk(G)+Xk(G), where G is a P4-free graph of order p and k = 1 or 2.
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spelling curtin-20.500.11937-119442017-03-08T13:12:21Z The Nordhaus-Gaddum problem for the k-defective chromatic number of a P4-free graph Achuthan, Nirmala Achuthan, Narasimaha Simanihuruk, M. A graph is (m, k)-colourable if its vertices can be coloured with m colours such that the maximum degree of the subgraph induced on vertices receiving the same colour is at most k. The k-defective chromatic number Xk(G) of a graph G is the least positive integer m for which G is (m, k)-colourable. The Nordhaus-Gaddum problem is to find sharp bounds for Xk(G)+Xk(G) and Xk(G). Xk(G) over the set of all graphs of order p where G is the complement of the graph G. In this paper we obtain a sharp upper bound for Xk(G)+Xk(G), where G is a P4-free graph of order p and k = 1 or 2. 2011 Journal Article http://hdl.handle.net/20.500.11937/11944 Centre for Discrete Mathematics and Computing restricted
spellingShingle Achuthan, Nirmala
Achuthan, Narasimaha
Simanihuruk, M.
The Nordhaus-Gaddum problem for the k-defective chromatic number of a P4-free graph
title The Nordhaus-Gaddum problem for the k-defective chromatic number of a P4-free graph
title_full The Nordhaus-Gaddum problem for the k-defective chromatic number of a P4-free graph
title_fullStr The Nordhaus-Gaddum problem for the k-defective chromatic number of a P4-free graph
title_full_unstemmed The Nordhaus-Gaddum problem for the k-defective chromatic number of a P4-free graph
title_short The Nordhaus-Gaddum problem for the k-defective chromatic number of a P4-free graph
title_sort nordhaus-gaddum problem for the k-defective chromatic number of a p4-free graph
url http://hdl.handle.net/20.500.11937/11944