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A211943 Number of distinct regular languages over 3-ary alphabet, whose minimum regular expression has reverse Polish length n. 0
5, 3, 15, 33, 106, 361, 1012, 3859, 11655, 43431 (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], 2012.
CROSSREFS
Sequence in context: A185733 A073677 A223535 * A189237 A301494 A053371
Adjacent sequences: A211940 A211941 A211942 * A211944 A211945 A211946
KEYWORD
nonn,hard
AUTHOR
Hermann Gruber, Apr 26 2012
STATUS
approved

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Last modified May 25 14:05 EDT 2024. Contains 372788 sequences. (Running on oeis4.)