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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

Table of n, a(n) for n=1..105.

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 have also length 2 and therefore a(3)=a(4)=2.

CROSSREFS

Cf. A000002, A049705.

Sequence in context: A164295 A035214 A071292 * A246144 A192763 A001285

Adjacent sequences:  A088566 A088567 A088568 * A088570 A088571 A088572

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Nov 17 2003

STATUS

approved

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Last modified December 11 04:17 EST 2016. Contains 279034 sequences.