A100428 Bisection of Kolakoski sequence A000002.

1, 2, 1, 1, 2, 2, 1, 2, 1, 2, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 2, 1, 2, 2, 1, 2, 2, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 2, 1, 2, 1, 2, 2, 1, 1, 2, 1, 2, 1, 1, 2, 2, 1, 2, 2, 1, 1, 2, 1, 2, 2, 1, 2, 2, 1, 1, 2, 1, 2, 2, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 2, 1

Offset: 1

Author

N. J. A. Sloane, Nov 20 2004

Keywords

• nonn
• easy

Comments

Lengths of runs of ones in A000002. - Reinhard Zumkeller, Aug 03 2013

As in the Kolakoski sequence itself, the length of runs in this sequence is 1 or 2 : a run X,X,X is not possible, since it would imply X,Y,X,Y,X in the Kolakoski sequence, which in turn would imply 1, 1, 1 somewhere before (one Y, one X, one Y) which is not possible. - Jean-Christophe Hervé, Oct 04 2014

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A100429, A216345.

Programs

Haskell

a100428 n = a100428_list !! n
a100428_list = f a000002_list where f (u:_:us) = u : f us
-- Reinhard Zumkeller, Aug 03 2013

Extensions

More terms from Joshua Zucker, May 12 2006

Offset changed by Reinhard Zumkeller, Aug 03 2013