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Closures which preserve finiteness in families of languages

โœ Scribed by Gene F. Rose

Publisher
Elsevier Science
Year
1968
Tongue
English
Weight
808 KB
Volume
2
Category
Article
ISSN
0022-0000

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โœฆ Synopsis

Each set of operations selected from union, intersection, complement, star, quotients, derivatives, word-reversal, and homomorphisms is investigated with respect to its closure of an arbitrary family of word-sets, as well as to its closure of an arbitrary family of regular languages. Certain sets are Shown to produce a finite closure for every finite family of word-sets; others, to produce a finite closure only for every finite family of regular languages; in either case, the closure for a given family of regular languages can be calculated by algorithm. For a third class of sets, the closure is not necessarily finite even for finite families of regular languages.

๐Ÿ“œ SIMILAR VOLUMES

Closure-preserving families of compact s
Closure-preserving families of compact sets
โœ H.B. Potoczny ๐Ÿ“‚ Article ๐Ÿ“… 1973 ๐Ÿ› Elsevier Science โš– 750 KB

In [ 31, Tamano raised the question of whether or not a space which admits a closurepreserving cova'r of compact sets is nzce:ssari!y paracon+:t. b cn~~etexamplc to this oonjectuse was given in 161: a completely rqular 1'2 space having a t losIre-preserving cover by compact sets (in fact, by finite