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A088569 Anti-Kolakoski sequence (sequence of run lengths never coincides with the sequence itself). 3
1, 1, 2, 2, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 2, 1, 1, 2, 1, 2, 2, 1, 2, 1, 1, 2, 2, 1, 2, 2, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 1, 2, 2, 1, 2, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 2, 1, 2, 1, 1, 2, 1, 2, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 2, 1, 1, 2, 1, 2, 2, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
Unique infinite word defined on alphabet {1,2} satisfying: a(1)=1, if a(n)=2 length of n-th run is 1, if a(n)=1 length of n-th run is 2. Kolakoski sequence satisfies the opposite definition: K(1)=1, if K(n)=2 length of n-th run is 2, if K(n)=1 length of n-th run is 1.
Equals A049705 without the first term. - Jean-Christophe Hervé, Nov 10 2014
LINKS
FORMULA
a(n) = 3 - A000002(n+1) = A049705(n+1).
EXAMPLE
a(1)=1 hence first run must have length 2 and necessarily a(2)=1. Now second run must also have length 2 and therefore a(3) = a(4) = 2.
CROSSREFS
Sequence in context: A164295 A035214 A071292 * A246144 A192763 A001285
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Nov 17 2003
STATUS
approved

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Last modified March 18 22:56 EDT 2024. Contains 370952 sequences. (Running on oeis4.)