𝔖 Bobbio Scriptorium
✦   LIBER   ✦

5-chromatic steiner triple systems

✍ Scribed by Jean Fugère; Lucien Haddad; David Wehlau


Publisher
John Wiley and Sons
Year
1994
Tongue
English
Weight
791 KB
Volume
2
Category
Article
ISSN
1063-8539

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

We show that, up to an automorphism, there is a unique independent set in PG(5,2) that meets every hyperplane in 4 points or more. Using this result, we show that PG(5,2) is a 5‐chromatic STS. Moreover, we construct a 5‐chromatic STS(v) for every admissible v ≥ 127. © 1994 John Wiley & Sons, Inc.


📜 SIMILAR VOLUMES


On the chromatic numbers of Steiner trip
✍ Lucien Haddad 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 188 KB 👁 2 views

Geometric properties are used to determine the chromatic number of AG(4, 3) and to derive some important facts on the chromatic number of PG(n, 2). It is also shown that a 4-chromatic STS(v) exists for every admissible order v ≥ 21.

Star chromatic numbers of hypergraphs an
✍ L. Haddad; H. Zhou 📂 Article 📅 1995 🏛 Elsevier Science 🌐 English ⚖ 635 KB

The concept of star chromatic number of a graph, introduced by Vince ( ) is a natural generalization of the chromatic number of a graph. This concept was studied from a pure combinatorial point of view by . In this paper we introduce strong and weak star chromatic numbers of uniform hypergraphs and

Balanced Steiner Triple Systems
✍ Charles Colbourn; Lucien Haddad; Václav Linek 📂 Article 📅 1997 🏛 Elsevier Science 🌐 English ⚖ 302 KB

and v 15, a 3-chromatic Steiner triple system of order v all of whose 3-colorings are equitable. 1997 Academic Press ## 1. Introduction A Steiner triple system of order v (briefly STS(v)) is a pair (X, B), where X is a v-element set and B is a collection of 3-subsets of X (triples), such that eve

Halving Steiner triple systems
✍ Pramod K. Das; Alexander Rosa 📂 Article 📅 1992 🏛 Elsevier Science 🌐 English ⚖ 805 KB