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A211942
Number of distinct finite languages over binary alphabet, whose minimum regular expression has reverse Polish length 2n-1.
0
4, 7, 25, 109, 514, 2641, 14354, 81325, 475936, 2854145
OFFSET
1,1
LINKS
Hermann Gruber, Jonathan Lee, and Jeffrey Shallit, Enumerating regular expressions and their languages, arXiv:1204.4982v1 [cs.FL], 2012.
CROSSREFS
Sequence in context: A276288 A219700 A151348 * A110413 A075686 A077441
KEYWORD
nonn,hard
AUTHOR
Hermann Gruber, Apr 26 2012
STATUS
approved