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A211953
Number of distinct regular languages over 4-ary alphabet, whose minimum regular expression has ordinary length n.
0
6, 20, 102, 520, 2628, 13482, 68747, 354500, 1840433
OFFSET
1,1
LINKS
Hermann Gruber, Jonathan Lee, and Jeffrey Shallit, Enumerating regular expressions and their languages, arXiv:1204.4982v1 [cs.FL]
CROSSREFS
Sequence in context: A333048 A200538 A238118 * A266846 A207819 A297974
KEYWORD
nonn,hard
AUTHOR
Hermann Gruber, Apr 26 2012
STATUS
approved