Abstract
Za delno kocko ▫$G$▫ ima ▫$\tau$▫-graph ▫$G^\tau$▫ ekvivalenčne razrede Djokovic-Winklerjeve relacije kot vozlišča, pri čemer sta razreda ▫$E$▫ in ▫$F$▫ sosednja, če neki povezavi ▫$e \in E$▫ in ▫$f \in F$▫ inducirata konveksno pot ▫$P_3$▫. Dokazano je, da za vsak graf $G$ obstaja medianski graf ▫$M$▫, tako da velja ▫$G = M^\tau$▫, da je ▫$G^\tau$▫ povezan natanko tedaj, ko je ▫$G$▫ pragraf glede na kartezični produkt grafov in da je ▫$\tau$▫-graf medianskega grafa ▫$G$▫ brez ▫$K_n$▫ natanko tedaj, ko ▫$G$▫ ne vsebuje konveksnega ▫$K_{1,n}$▫.
Keywords
matematika;teorija grafov;delne kocke;medianski grafi;kartezični produkt grafov;mathematics;graf theory;partial cubes;median graphs;Cartesian product graphs;
Data
Language: |
English |
Year of publishing: |
2007 |
Typology: |
1.01 - Original Scientific Article |
Organization: |
UL FMF - Faculty of Mathematics and Physics |
UDC: |
519.17 |
COBISS: |
14252377
|
ISSN: |
0195-6698 |
Views: |
37 |
Downloads: |
27 |
Average score: |
0 (0 votes) |
Metadata: |
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Other data
Secondary language: |
Slovenian |
Secondary title: |
Delne kocke in njihovi [tau]-grafi |
Secondary abstract: |
The ▫$\tau$▫-graph ▫$G^\tau$▫ of a partial cube ▫$G$▫ has the equivalence classes of the Djokovic-Winkler relation as vertices, two classes ▫$E$▫ and ▫$F$▫ being adjacent if some edges ▫$e \in E$▫ and ▫$f \in F$▫ induce a convex ▫$P_3$▫. It is shown that for every graph ▫$G$▫ there exists a median graph ▫$M$▫ such that ▫$G = M^\tau$▫, that ▫$G^\tau$▫ is connected if and only if ▫$G$▫ is a Cartesian prime graph, and that for a median graph ▫$G$▫ its ▫$\tau$▫-graph is ▫$K_n$▫-free if and only if ▫$G$▫ contains no convex ▫$K_{1,n}$▫. |
Secondary keywords: |
matematika;teorija grafov;delne kocke;medianski grafi;kartezični produkt grafov; |
URN: |
URN:SI:UM: |
Type (COBISS): |
Not categorized |
Pages: |
str. 1037-1042 |
Volume: |
ǂVol. ǂ28 |
Issue: |
ǂno. ǂ4 |
Chronology: |
2007 |
ID: |
1473038 |