𝔖 Bobbio Scriptorium
✦   LIBER   ✦

A hole-size bound for incomplete t-wise balanced designs

✍ Scribed by Donald L. Kreher; Rolf S. Rees


Publisher
John Wiley and Sons
Year
2001
Tongue
English
Weight
140 KB
Volume
9
Category
Article
ISSN
1063-8539

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

An incomplete t‐wise balanced design of index Ξ» is a triple (X,H,ℬ︁) where X is a υ–element set, H is a subset of X called the hole, and B is a collection of subsets of X called blocks, such that, every t‐element subset of X is either in H or in exactly Ξ» blocks, but not both. If H is a hole in an incomplete t‐wise balanced design of order Ο… and index Ξ», then |H| ≀ Ο…/2 if t is odd and |H| ≀ (Ο…β€‰βˆ’β€‰1)/2 if t is even. In particular, this result establishes the validity of Kramer's conjecture that the maximal size of a block in a Steiner t‐wise balanced design is at most Ο…/2 if t is odd and at most (Ο…βˆ’1)/2 when t is even. Β© 2001 John Wiley & Sons, Inc. J Combin Designs 9: 269–284, 2001


πŸ“œ SIMILAR VOLUMES


A block-size bound for Steiner 6–wise ba
✍ Michael Ira; Earl S. Kramer πŸ“‚ Article πŸ“… 2000 πŸ› John Wiley and Sons 🌐 English βš– 91 KB πŸ‘ 1 views

A t-wise balanced design (tBD) of type t-vY KY ! is a pair XY Bwhere X is a velement set of points and B is a collection of subsets of X called blocks with the property that the size of every block is in K and every t-element subset of X is contained in exactly ! blocks. If K is a set of positive in

Further results on the maximum size of a
✍ I. Adamczak; D. L. Kreher; A. C. H. Ling; R. S. Rees πŸ“‚ Article πŸ“… 2002 πŸ› John Wiley and Sons 🌐 English βš– 192 KB πŸ‘ 1 views

## Abstract Kreher and Rees 3 proved that if __h__ is the size of a hole in an incomplete balanced design of order Ο… and index Ξ» having minimum block size $k \ge t+1$, then, They showed that when __t__ = 2 or 3, this bound is sharp infinitely often in that for each __h__ β‰₯ __t__ and each __k__ β‰₯ _