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A079730 Kolakoski variation using (1,2,3,4) starting with 1,2. 2
1, 2, 2, 3, 3, 4, 4, 4, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 1, 2, 3, 4, 4, 1, 1, 2, 2, 3, 3, 4, 4, 4, 1, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 4, 4, 1, 1, 1, 1, 2, 2, 2, 2, 3, 3, 3, 3, 4, 1, 1, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 1, 2, 3, 3, 4, 4, 1, 1, 1, 2, 2, 2, 3, 3, 3, 3, 4, 4, 4, 4, 1, 1, 1, 1, 2, 3, 4, 1, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(1)=1 then a(n) is the length of n-th run. This kind of Kolakoski variation using(1,2,3,4,...,m) as m grows reaches the Golomb's sequence A001462.

LINKS

Ivan Neretin, Table of n, a(n) for n = 1..10000

FORMULA

Partial sum sequence is expected to be asymptotic to 5/2*n.

EXAMPLE

Sequence begins: 1,2,2,3,3,4,4,4,1,1,1,2,2,2,2,3,3,3,3, read it as: (1),(2,2),(3,3),(4,4,4),(1,1,1),(2,2,2,2),(3,3,3,3),... then count the terms in parentheses to get: 1,2,2,3,3,4,4,.. which is the same sequence.

MATHEMATICA

seed = {1, 2, 3, 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, 41}];

w

CROSSREFS

Cf. A000002.

Sequence in context: A252759 A085654 A074719 * A035486 A282347 A172397

Adjacent sequences:  A079727 A079728 A079729 * A079731 A079732 A079733

KEYWORD

nonn

AUTHOR

Benoit Cloitre, Feb 17 2003

EXTENSIONS

Corrected by Ivan Neretin, Apr 01 2015

STATUS

approved

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Last modified March 26 16:31 EDT 2017. Contains 284137 sequences.