Editing Sequence (section)

===Streams===
Infinite sequences of [[numerical digit|digits]] (or [[character (computing)|characters]]) drawn from a [[finite set|finite]] [[alphabet (computer science)|alphabet]] are of particular interest in [[theoretical computer science]]. They are often referred to simply as ''sequences'' or ''[[Stream (computing)|streams]]'', as opposed to finite ''[[String (computer science)#Formal theory|strings]]''. Infinite binary sequences, for instance, are infinite sequences of [[bit]]s (characters drawn from the alphabet {0, 1}). The set ''C'' = {0, 1}<sup>∞</sup> of all infinite binary sequences is sometimes called the [[Cantor space]].

An infinite binary sequence can represent a [[formal language]] (a set of strings) by setting the ''n''&thinsp;th bit of the sequence to 1 if and only if the ''n''&thinsp;th string (in [[shortlex order]]) is in the language. This representation is useful in the [[Cantor's diagonal argument|diagonalization method]] for proofs.<ref name=Oflazer2011>{{cite web|last1=Oflazer|first1=Kemal|title=FORMAL LANGUAGES, AUTOMATA AND COMPUTATION: DECIDABILITY|url=http://www.andrew.cmu.edu/user/ko/pdfs/lecture-15.pdf|website=cmu.edu|publisher=Carnegie-Mellon University|access-date=24 April 2015|archive-date=29 May 2015|archive-url=https://web.archive.org/web/20150529101719/http://www.andrew.cmu.edu/user/ko/pdfs/lecture-15.pdf|url-status=live}}</ref>