In a Steiner triple system STS(v) = (V, B), for each pair {a, b} โ V, the cycle graph G a,b can be defined as follows. The vertices of G a,b are V \ {a, b, c} where {a, b, c} โ B. {x, y} is an edge if either {a, x, y} or {b, x, y} โ B. The Steiner triple system is said to be perfect if the cycle gra
Some results on quadrilaterals in Steiner triple systems
โ Scribed by D.R. Stinson; Y.J. Wei
- Publisher
- Elsevier Science
- Year
- 1992
- Tongue
- English
- Weight
- 792 KB
- Volume
- 105
- Category
- Article
- ISSN
- 0012-365X
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โฆ Synopsis
Stinson, D.R., Y.J. Wei, Some results on quadrilaterals in Steiner triple systems, Discrete Mathematics 105 (1992) 207-219.
In this paper, we study quadrilaterals in Steiner triple systems. We present two recursive constructions for Steiner triple systems having no quadrilaterals.
We also consider the maximum number of quadrilaterals a Steiner triple system of any given order can have. The upper bound is reached precisely when the Steiner triple system is the projective space PG(d, 2). Some recursive constructions for Steiner triple systems having 'many' quadrilaterals are also presented.
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