Median and quasi-median direct products of graphs

• Autorzy: Boštjan Brešar , Pranava K. Jha , Sandi Klavžar , Blaž Zmazek
• Języki publikacji: EN

Abstrakty

EN

Median graphs are characterized among direct products of graphs on at least three vertices. Beside some trivial cases, it is shown that one component of G×P₃ is median if and only if G is a tree in that the distance between any two vertices of degree at least 3 is even. In addition, some partial results considering median graphs of the form G×K₂ are proved, and it is shown that the only nonbipartite quasi-median direct product is K₃×K₃.

Słowa kluczowe

EN

median graph; direct product; quasi-median graph; isometric embeddings; convexity

Kategorie tematyczne

• 05C12: Distance in graphs
• 05C75: Structural characterization of families of graphs

• Wydawca: De Gruyter Open
• Czasopismo: Discussiones Mathematicae Graph Theory
• Rocznik: 2005
• Tom: 25
• Numer: 1-2
• Strony: 183-196

Daty

wydano

2005

otrzymano

2003-11-29

poprawiono

2004-09-01

Twórcy

autor

Boštjan Brešar

• University of Maribor, FEECS, Smetanova 17, 2000 Maribor, Slovenia

autor

Pranava K. Jha

• Department of Computer Science, St. Cloud State University, 720 Fourth Ave. S., St. Cloud, MN 56301, USA

autor

Sandi Klavžar

• Department of Mathematics and Computer Science, PEF, University of Maribor, Koroska 160, 2000 Maribor, Slovenia

autor

Blaž Zmazek

• University of Maribor, FME, Smetanova 17, 2000 Maribor, Slovenia

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Identyfikatory

DOI

10.7151/dmgt.1271