A074262 Positions of '11' in Kolakoski sequence A000002.

4, 13, 16, 22, 28, 31, 40, 48, 51, 58, 67, 70, 78, 85, 94, 97, 103, 112, 115, 121, 124, 130, 133, 140, 148, 157, 160, 167, 175, 178, 184, 190, 193, 201, 208, 217, 220, 226, 229, 238, 244, 247, 253, 256, 265, 271, 274, 283, 291, 294, 303, 310, 319, 322, 328

Offset

1,1

Links

Nathaniel Johnston, Table of n, a(n) for n = 1..10000

Example

Kolakoski sequence begins 1,2,2,1,1,2,1,2,2,1,2,2,1,1,... so 4 and 13 are in this sequence.

Mathematica

a2 = {1, 2, 2}; Do[ a2 = Join[a2, {1 + Mod[n - 1, 2]}], {n, 3, 300}, {i, 1, a2[[n]]}]; Split[a2] /. {1, 1} -> {0, 1} // Flatten // Position[#, 0]& // Flatten (* Jean-François Alcover, Jun 18 2013 *)

Crossrefs

Cf. A074263.

Sequence in context: A287361 A165336 A031181 * A297363 A031208 A228137

Adjacent sequences: A074259 A074260 A074261 * A074263 A074264 A074265

Keyword

nonn,easy

Author

Jon Perry, Sep 20 2002

Extensions

Extended and offset changed by Nathaniel Johnston, May 02 2011

Status

approved