

A116909


Start with the sequence 2322322323222323223223 and extend by always appending the curling number (cf. A094004).


5



2, 3, 2, 2, 3, 2, 2, 3, 2, 3, 2, 2, 2, 3, 2, 3, 2, 2, 3, 2, 2, 3, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 3, 2, 2, 2, 3, 2, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 3, 2, 2, 2, 3, 2
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OFFSET

1,1


COMMENTS

The (unproved) Curling Number Conjecture is that any starting sequence eventually leads to a "1". The starting sequence used here extends for a total of 142 steps before reaching 1. After than it continues as A090822.
Benjamin Chaffin has found that in a certain sense this is the best of all 2^45 starting sequences of at most 44 2's and 3's.
Note that a(362) = 4. The sequence is unbounded, but a(n) = 5 is not reached until about n = 10^(10^23)  see A090822.


LINKS

N. J. A. Sloane, Table of n, a(n) for n = 1..500
F. J. van de Bult, D. C. Gijswijt, J. P. Linderman, N. J. A. Sloane and Allan Wilks, A SlowGrowing Sequence Defined by an Unusual Recurrence, J. Integer Sequences, Vol. 10 (2007), #07.1.2.
F. J. van de Bult, D. C. Gijswijt, J. P. Linderman, N. J. A. Sloane and Allan Wilks, A SlowGrowing Sequence Defined by an Unusual Recurrence [pdf, ps].
N. J. A. Sloane, Fortran program
Index entries for sequences related to curling numbers


CROSSREFS

Cf. A094004, A090822, A174998. Sequence of run lengths: A161223.
Sequence in context: A143393 A269111 A166497 * A182006 A085239 A242872
Adjacent sequences: A116906 A116907 A116908 * A116910 A116911 A116912


KEYWORD

nonn,nice


AUTHOR

N. J. A. Sloane, Jan 15 2009, based on email from Benjamin Chaffin, Apr 09 2008 and Dec 04 2009


STATUS

approved



