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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
OFFSET
1,1
LINKS
Hermann Gruber, Jonathan Lee, and Jeffrey Shallit, Enumerating regular expressions and their languages, arXiv:1204.4982v1 [cs.FL]
CROSSREFS
Sequence in context: A362727 A012665 A317076 * A331405 A005787 A012343
KEYWORD
nonn,hard
AUTHOR
Hermann Gruber, Apr 25 2012
STATUS
approved