Strict colourings for classes of steiner triple systems

L. Milazzo, Z. Tuza

Research output: Contribution to journalArticle

33 Citations (Scopus)

Abstract

We investigate the largest number of colours, called upper chromatic number and denoted χ̄(ℋ), that can be assigned to the vertices (points) of a Steiner triple system ℋ in such a way that every block H ∈ ℋ contains at least two vertices of the same colour. The exact value of χ̄ is determined for some classes of triple systems, and it is observed further that optimal colourings with the same number of colours exist also under the additional assumption that no monochromatic block occurs. Examples show, however, that the cardinalities of the colour classes in the latter case are more strictly determined.

Original languageEnglish
Pages (from-to)233-243
Number of pages11
JournalDiscrete Mathematics
Volume182
Issue number1-3
Publication statusPublished - Mar 1 1998

Fingerprint

Steiner Triple System
Color
Triple System
Chromatic number
Cardinality
Strictly
Class

ASJC Scopus subject areas

  • Discrete Mathematics and Combinatorics
  • Theoretical Computer Science

Cite this

Strict colourings for classes of steiner triple systems. / Milazzo, L.; Tuza, Z.

In: Discrete Mathematics, Vol. 182, No. 1-3, 01.03.1998, p. 233-243.

Research output: Contribution to journalArticle

Milazzo, L. ; Tuza, Z. / Strict colourings for classes of steiner triple systems. In: Discrete Mathematics. 1998 ; Vol. 182, No. 1-3. pp. 233-243.
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