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A211938 Number of distinct finite languages over 4-ary alphabet, whose minimum regular expression has alphabetic width n. 0
2, 8, 112, 2164, 51008, 1346924 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..6.

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

CROSSREFS

Sequence in context: A012554 A012665 A317076 * A331405 A005787 A012343

Adjacent sequences: A211935 A211936 A211937 * A211939 A211940 A211941

KEYWORD

nonn,hard

AUTHOR

Hermann Gruber, Apr 25 2012

STATUS

approved

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Last modified December 9 14:35 EST 2022. Contains 358700 sequences. (Running on oeis4.)