The pre-hull number and lexicographic product

Abstract

Nedavno sta Polat in Sabidussi v [On the geodesic pre-hull number of a graph, Europ. J. Combin. 30 (2009), 1205--1220] vpeljala invarianto ko-točkovno pred-ovojnično število ▫$\mathrm{ph}(G)$▫ grafa ▫$G$▫, ki meri nekonveksnost konveksnega prostora. Vpeljemo podobno invarianto imenovano konveksno pred-ovojnično število, ki je naravna zgornja meja za ko-točkovno pred-ovojnično število. Obe invarianti študiramo na leksikografskem produktu in podamo natančne vrednosti za obe invarianti glede na lastnosti faktorjev.

Keywords

matematika;teorija grafov;pred-ovojnično število;geodetska konveksnost;leksikografski produkt;mathematics;graph theory;pre-hull number;geodesic convexity;lexicographic product;

Data

Language:	English
Year of publishing:	2012
Typology:	1.08 - Published Scientific Conference Contribution
Organization:	UM FERI - Faculty of Electrical Engineering and Computer Science
UDC:	519.17
COBISS:	16280921
ISSN:	0012-365X
Views:	360
Downloads:	19
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Pred-ovojnično število in leksikografski produkt
Secondary abstract:	Recently the invariant (copoint) pre-hull number ▫$\mathrm{ph}(G)$▫ of a graph ▫$G$▫ that measures the nonconvexity of a convex space was introduced by Polat and Sabidussi [On the geodesic pre-hull number of a graph, Europ. J. Combin. 30 (2009), 1205--1220]. We introduce a similar invariant called convex pre-hull number which is a natural upper bound for the copoint pre-hull number and consider in this work both on the lexicographic product of graphs. We present exact values with respect to properties of the factors.
Secondary keywords:	matematika;teorija grafov;pred-ovojnično število;geodetska konveksnost;leksikografski produkt;
URN:	URN:SI:UM:
Type (COBISS):	Not categorized
Pages:	Str. 2153-2157
ID:	1476538