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A211944
Number of distinct finite languages over 3-ary alphabet, whose minimum regular expression has reverse Polish length 2n-1.
0
5, 15, 85, 589, 4512, 37477, 328718, 2998039
(list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Table of n, a(n) for n=1..8.
Hermann Gruber, Jonathan Lee, and Jeffrey Shallit, Enumerating regular expressions and their languages, arXiv:1204.4982v1 [cs.FL], 2012.
CROSSREFS
Sequence in context: A165625 A058820 A054363 * A336998 A276474 A362577
Adjacent sequences: A211941 A211942 A211943 * A211945 A211946 A211947
KEYWORD
nonn,hard
AUTHOR
Hermann Gruber, Apr 26 2012
STATUS
approved

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Last modified September 30 13:07 EDT 2024. Contains 376364 sequences.
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