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A291798
Take n-th word over {1,2} listed in A291797 and apply the Post tag system described in A284116 (but adapted to the alphabet {1,2}); a(n) = preperiod (or threshold) of orbit of that word.
2
3, 4, 6, 2, 17, 15, 9, 11, 13, 14, 16, 12, 24, 10, 12, 19, 14, 23, 21, 4, 13, 9, 25, 11, 29, 27, 3, 7, 420, 25, 15, 24, 28, 6, 17, 19, 28, 4, 26, 21, 23, 419, 6, 417, 46, 24, 8, 5, 421, 26, 28, 415, 12, 413, 10, 44, 27, 10, 40, 22, 84, 411, 18, 20, 29, 9, 11
OFFSET
1,1
COMMENTS
Post's tag system maps a word w over {1,2} to w', where if w begins with 1, w' is obtained by appending 11 to w and deleting the first three letters, or if w begins with 2, w' is obtained by appending 2212 to w and deleting the first three letters.
We work over {1,2} rather than the official alphabet {0,1} because of the prohibition in the OEIS of terms (other than 0 itself) which begin with 0.
This is an analog of A284119 for the words in A291797.
LINKS
Lars Blomberg, Table of n, a(n) for n = 1..8190 (For terms in A291797 up to length 36.)
Peter R. J. Asveld, On a Post's System of Tag. Bulletin of the EATCS 36 (1988), 96-102. See Table 3.
CROSSREFS
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Sep 04 2017
EXTENSIONS
a(31)-a(67) from Lars Blomberg, Sep 08 2017
STATUS
approved