The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
The OEIS is supported by the many generous donors to the OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A270644 The sequence a of 1's and 2's starting with (1,2,2,2) such that a(n) is the length of the (n+2)nd run of a. 2
 1, 2, 2, 2, 1, 2, 2, 1, 1, 2, 2, 1, 2, 2, 1, 1, 2, 1, 2, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 1, 2, 2, 1, 1, 2, 1, 1, 2, 1, 2, 2, 1, 2, 1, 1, 2, 2, 1, 2, 2, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 2, 1, 1, 2, 1, 2, 2, 1, 2, 2, 1, 1, 2, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS See A270641 for a guide to related sequences. LINKS Clark Kimberling, Table of n, a(n) for n = 1..10000 EXAMPLE a(1) = 1, so the 3rd run has length 1, so a(5) must be 1 and a(6) = 2. a(2) = 2, so the 4th run has length 2, so a(7) = 2 and a(8) = 1. a(3) = 2, so the 5th run has length 2, so a(9) = 1and a(10) = 2. Globally, the runlength sequence is 1,3,1,2,2,2,1,2,2,1,1,2,2,1,2,2,..., and deleting the first 2 terms leaves the same sequence. MATHEMATICA a = {1, 2, 2, 2}; Do[a = Join[a, ConstantArray[If[Last[a] == 1, 2, 1], {a[[n]]}]], {n, 200}]; a (* Peter J. C. Moses, Apr 01 2016 *) CROSSREFS Cf. A000002, A006928, A022300, A270641. Sequence in context: A136690 A144703 A276825 * A361156 A097026 A189225 Adjacent sequences: A270641 A270642 A270643 * A270645 A270646 A270647 KEYWORD nonn,easy AUTHOR Clark Kimberling, Apr 06 2016 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified May 23 02:30 EDT 2024. Contains 372758 sequences. (Running on oeis4.)