In 1964, Kautz and Singleton (IEEE Trans. Inform. Theory 10 (1964), 363-377) introduced the superimposed code concept. A binary superimposed code of strength s is identified by the incidence matrix of a family of finite sets in which no set is covered by the union of s others (
Complexity of Recognizing Equal Unions in Families of Sets
โ Scribed by David P. Jacobs; Robert E. Jamison
- Publisher
- Elsevier Science
- Year
- 2000
- Tongue
- English
- Weight
- 87 KB
- Volume
- 37
- Category
- Article
- ISSN
- 0196-6774
No coin nor oath required. For personal study only.
โฆ Synopsis
A family of sets has the equal union property if there exist two nonempty disjoint subfamilies having equal unions and has the full equal union property if, in addition, all sets are included. Both recognition problems are NP-complete even when restricted to families for which the cardinality of every set is at most three. Both problems can be solved in polynomial time when restricted to families having a bounded number of sets with cardinality greater than two. A corollary is that deciding if a graph has two disjoint edge covers is in P.
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