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A156256 Number of 1's separating successive 2's in the Kolakoski sequence A000002. 1
0, 2, 1, 0, 1, 0, 2, 2, 0, 1, 2, 1, 0, 2, 2, 1, 0, 1, 0, 2, 1, 0, 1, 2, 2, 0, 1, 0, 2, 1, 0, 1, 0, 2, 2, 1, 0, 1, 2, 0, 1, 0, 2, 1, 0, 1, 0, 2, 2, 0, 1, 2, 1, 0, 1, 0, 2, 2, 1, 0, 2, 2, 0, 1, 2, 2, 0, 1, 0, 2, 1, 0, 1, 2, 0, 1, 0, 1, 2, 2, 0, 1, 0, 2, 1, 0, 1, 2, 2, 0, 1, 2, 1, 0, 2, 2, 1, 0, 1, 2 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

After deleting zeros in this sequence it remains the bisection of Kolakoski sequence A000002(2n+1) n>=1 given by A100428.

This is because A100428 gives the lengths of runs of 1's in Kolakoski sequence. - Jean-Christophe Hervé, Oct 14 2014

The Kolakovski sequence can be obtained back (except the initial 1) by the following substitution rules: insert 2 between two successive nonzero values and 0 -> 22, 1 -> 1, 2 -> 11. - Jean-Christophe Hervé, Oct 14 2014

LINKS

Table of n, a(n) for n=1..100.

FORMULA

a(n)=A078649(n+1)-A078649(n)-2.

EXAMPLE

The Kolakoski sequence begins with 122112122122, thus this one begins 0, 2, 1, 0, 1, 0. - Jean-Christophe Hervé, Oct 14 2014

CROSSREFS

Cf. A000002, A100428, A248806.

Sequence in context: A162514 A166347 A055300 * A029406 A158461 A281498

Adjacent sequences:  A156253 A156254 A156255 * A156257 A156258 A156259

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Feb 07 2009

EXTENSIONS

Better name from Jean-Christophe Hervé, Oct 15 2014

STATUS

approved

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Last modified January 17 20:36 EST 2020. Contains 330987 sequences. (Running on oeis4.)