This site is supported by donations to The OEIS Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A071907 Kolakoski-(1,4) sequence: a(n) is length of n-th run. 7
 1, 4, 4, 4, 4, 1, 1, 1, 1, 4, 4, 4, 4, 1, 1, 1, 1, 4, 1, 4, 1, 4, 4, 4, 4, 1, 1, 1, 1, 4, 4, 4, 4, 1, 1, 1, 1, 4, 1, 4, 1, 4, 4, 4, 4, 1, 4, 4, 4, 4, 1, 4, 4, 4, 4, 1, 1, 1, 1, 4, 4, 4, 4, 1, 1, 1, 1, 4, 1, 4, 1, 4, 4, 4, 4, 1, 1, 1, 1, 4, 4, 4, 4, 1, 1, 1, 1, 4, 1, 4, 1, 4, 4, 4, 4, 1, 4, 4, 4, 4, 1, 4, 4, 4, 4 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS 1444411, 14444111144441111414144441111 are primes. - Vincenzo Librandi, Mar 02 2016 LINKS Ivan Neretin, Table of n, a(n) for n = 1..10000 Michael Baake and Bernd Sing, Kolakoski-(3,1) is a (deformed) model set, arXiv:math/0206098 [math.MG], 2002-2003. MATHEMATICA seed = {1, 4}; w = {}; i = 1; Do[w = Join[w, Array[seed[[Mod[i - 1, Length[seed]] + 1]] &, If[i > Length[w], seed, w][[i]]]]; i++, {n, 42}]; w (* Ivan Neretin, Apr 02 2015 *) CROSSREFS Cf. A000002, A071820, A064353, A071928, A071942. Sequence in context: A274947 A279406 A171408 * A172369 A190338 A199177 Adjacent sequences:  A071904 A071905 A071906 * A071908 A071909 A071910 KEYWORD nonn,easy AUTHOR STATUS approved

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

Last modified September 19 04:39 EDT 2019. Contains 327187 sequences. (Running on oeis4.)