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A211946 Number of distinct finite languages over 4-ary alphabet, whose minimum regular expression has reverse Polish length 2n-1. 1
6, 26, 202, 1917, 20251, 231152, 2780936 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Table of n, a(n) for n=1..7.
Hermann Gruber, Jonathan Lee, and Jeffrey Shallit, Enumerating regular expressions and their languages, arXiv:1204.4982v1 [cs.FL], 2012.
CROSSREFS
Bisection of A211945.
Sequence in context: A049040 A103649 A053946 * A027283 A009639 A323868
Adjacent sequences: A211943 A211944 A211945 * A211947 A211948 A211949
KEYWORD
nonn,hard,more
AUTHOR
Hermann Gruber, Apr 26 2012
STATUS
approved

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Last modified June 4 03:29 EDT 2024. Contains 373089 sequences. (Running on oeis4.)