Language-theoretic complexity of disjunctive sequences
نویسندگان
چکیده
منابع مشابه
Language-theoretic Complexity of Disjunctive Sequences
A sequence over an alphabet Σ is called disjunctive [13] if it contains all possible finite strings over Σ as its substrings. Disjunctive sequences have been recently studied in various contexts, e.g. [12, 9]. They abound in both category and measure senses [5]. In this paper we measure the complexity of a sequence x by the complexity of the language P (x) consisting of all prefixes of x. The l...
متن کاملComplexity of Disjunctive Sequences
A sequence over an alphabet Σ is called disjunctive [13] if it contains all possible finite strings over Σ as its substrings. Disjunctive sequences have been recently studied in various contexts, e.g. [12, 9]. They abound in both category and measure senses [5]. In this paper we measure the complexity of a sequence x by the complexity of the language P (x) consisting of all prefixes of x. The l...
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The present paper proposes a generalisation of the notion of disjunctive (or rich) sequence, that is, of an infinite sequence of letters having each finite sequence as a subword. Our aim is to give a reasonable notion of disjunctiveness relative to a given set of sequences F . We show that a definition like “every subword which occurs at infinitely many different positions in sequences in F has...
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ژورنال
عنوان ژورنال: Discrete Applied Mathematics
سال: 1997
ISSN: 0166-218X
DOI: 10.1016/s0166-218x(97)00061-9