Abstract
For an ordering of the blocks of a design, the point sum of an element is the sum of the indices of blocks containing that element. Block labelling for popularity asks for the point sums to be as equal as possible. For Steiner systems of order v and strength t in general, the average point sum is O(v2t-1) ; under various restrictions on block partitions of the Steiner system, the difference between the largest and smallest point sums is shown to be O(v(t+1)/2log v). Indeed for Steiner triple systems, direct and recursive constructions are given to establish that systems exist with all point sums equal for more than two thirds of the admissible orders.
Original language | English (US) |
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Pages (from-to) | 2373-2395 |
Number of pages | 23 |
Journal | Designs, Codes, and Cryptography |
Volume | 89 |
Issue number | 10 |
DOIs | |
State | Published - Oct 2021 |
Keywords
- Group-divisible design
- Hill-climbing algorithm
- Steiner system
- Steiner triple system
- Transversal design
ASJC Scopus subject areas
- Theoretical Computer Science
- Computer Science Applications
- Discrete Mathematics and Combinatorics
- Applied Mathematics