A118270 Decimal expansion of Kolakoski constant.

7, 9, 4, 5, 0, 7, 1, 9, 2, 7, 7, 9, 4, 7, 9, 2, 7, 6, 2, 4, 0, 3, 6, 2, 4, 1, 5, 6, 3, 6, 0, 4, 5, 6, 4, 6, 2, 9, 8, 5, 7, 7, 1, 0, 0, 9, 8, 8, 6, 0, 6, 9, 6, 7, 2, 6, 5, 8, 8, 6, 7, 3, 7, 1, 5, 3, 8, 1, 4, 7, 7, 5, 0, 2, 4, 6, 0, 5, 0, 1, 5, 3, 6, 4, 2, 3, 2, 9, 4, 9, 7, 3, 1, 8, 7, 4, 4, 9, 2, 2, 5, 9, 7, 6, 5

Offset

0,1

Links

Table of n, a(n) for n=0..104.

Rabie A. Mahmoud, Hardware Implementation of Binary Kolakoski Sequence, Research Gate, 2015.

Eric Weisstein's World of Mathematics, Kolakoski Sequence

Formula

Take the Kolakoski sequence (A000002) 1221121221.... Interpret the 2's as 1's and the 1's as 0's: 0110010110.... Interpret the result as a binary fraction: 0.110010110..._2.

Example

0.7945071927794792762...

Mathematica

A000002[n_] := (s = {1, 2, 2}; Do[AppendTo[s, Mod[k-1, 2] + 1], {k, 3, n}, {s[[k]]}] ; s); Take[ First[ RealDigits[ FromDigits[ {Rest[A000002[300] /. {1 -> 0, 2 -> 1}], 0}, 2]]], 105] (* Jean-François Alcover, Jul 28 2011 *)

Crossrefs

Cf. A000002.

Sequence in context: A102375 A216754 A303296 * A179292 A361972 A198756

Adjacent sequences: A118267 A118268 A118269 * A118271 A118272 A118273

Keyword

nonn,cons

Author

Eric W. Weisstein, Apr 21 2006

Status

approved