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%I #5 Mar 07 2016 06:15:55
%S 1,10,10,10,10,10,10,10,10,10,10,1,1,1,1,1,1,1,1,1,1,10,10,10,10,10,
%T 10,10,10,10,10,1,1,1,1,1,1,1,1,1,1,10,10,10,10,10,10,10,10,10,10,1,1,
%U 1,1,1,1,1,1,1,1,10,10,10,10,10,10,10,10,10,10,1,1,1
%N Kolakoski-(1,10) sequence: a(n) is length of n-th run.
%C No prime number with the union of many terms.
%H Michael Baake and Bernd Sing, <a href="http://arXiv.org/abs/math.MG/0206098">Kolakoski-(3,1) is a (deformed) model set</a>, arXiv:math/0206098 [math.MG], 2002-2003.
%t seed = {1, 10}; 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
%Y Cf. similar sequences listed in A269268.
%K nonn,easy
%O 1,2
%A _Vincenzo Librandi_, Mar 02 2016