The spectrum of support sizes for threefold triple systems

Charles Colbourn, Ebadollah S. Mahmoodian

Research output: Contribution to journalArticle

12 Citations (Scopus)

Abstract

The spectrum of possible numbers of distinct blocks in a threefold triple system of order v is determined. Let mυ = ⌊ υ(υ-1) 6⌋. A threefold triple system with υ ≡ 1, 3 (mod 6) elements can have any number of distinct blocks from, and only from, {mυ,mυ + 4, mυ + 6, mυ + 7,⋯, 3mυ} provided υ≠3, 7, 9. A threefold triple system with υ≡5 (mod 6) elements can have any number of distinct blocks from, and only from, {mυ + 7, mυ + 10, mυ + 11,⋯, 3mυ + 1}.

Original languageEnglish (US)
Pages (from-to)9-19
Number of pages11
JournalDiscrete Mathematics
Volume83
Issue number1
DOIs
StatePublished - Jul 1 1990
Externally publishedYes

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Triple System
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ASJC Scopus subject areas

  • Discrete Mathematics and Combinatorics
  • Theoretical Computer Science

Cite this

The spectrum of support sizes for threefold triple systems. / Colbourn, Charles; Mahmoodian, Ebadollah S.

In: Discrete Mathematics, Vol. 83, No. 1, 01.07.1990, p. 9-19.

Research output: Contribution to journalArticle

Colbourn, Charles ; Mahmoodian, Ebadollah S. / The spectrum of support sizes for threefold triple systems. In: Discrete Mathematics. 1990 ; Vol. 83, No. 1. pp. 9-19.
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