login
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
OFFSET
1,1
LINKS
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
KEYWORD
nonn,hard,more
AUTHOR
Hermann Gruber, Apr 26 2012
STATUS
approved