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A211952 Number of distinct finite languages over 3-ary alphabet, whose minimum regular expression has ordinary length n. 0
5, 9, 33, 117, 391, 1350, 4546, 15753, 55053, 196185 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..10.

Hermann Gruber, Jonathan Lee, and Jeffrey Shallit, Enumerating regular expressions and their languages, arXiv:1204.4982v1 [cs.FL]

CROSSREFS

Sequence in context: A323150 A116390 A028351 * A098640 A239546 A083832

Adjacent sequences:  A211949 A211950 A211951 * A211953 A211954 A211955

KEYWORD

nonn,hard

AUTHOR

Hermann Gruber, Apr 26 2012

STATUS

approved

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Last modified December 9 13:50 EST 2019. Contains 329877 sequences. (Running on oeis4.)