A156256 Number of 1's separating successive 2's in the Kolakoski sequence A000002.

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

Offset

1,2

Comments

After deleting 0's 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, A078649, A100428, A248806.

Sequence in context: A166347 A055300 A335392 * 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