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A095346
a(n) is the length of the n-th run of A095345.
3
3, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1, 1, 3, 1, 1, 1, 3, 1, 3, 1, 1
OFFSET
1,1
COMMENTS
This is the second sequence reached in the infinite process described in A066983 comment line.
(a(n)) is a morphic sequence, i.e., a letter to letter projection of a fixed point of a morphism. The morphism is 1->121,2->3,1,3->313. The fixed point is the fixed point 3131213131213... starting with 3. The letter-to-letter map is 1->1, 2->1, 3->3. See also COMMENTS of A108103. - Michel Dekking, Jan 06 2018
REFERENCES
F. M. Dekking: "What is the long range order in the Kolakoski sequence?" in: The Mathematics of Long-Range Aperiodic Order, ed. R. V. Moody, Kluwer, Dordrecht (1997), pp. 115-125.
FORMULA
a(n)=3 if n=1+2*floor(phi*k) for some k where phi=(1+sqrt(5))/2, else a(n)=1. [Benoit Cloitre, Mar 02 2009]
EXAMPLE
A095345 begins : 1,1,1,3,1,1,1,3,1,3,...,.. and length or runs of 1's and 3's are 3,1,3,1,1,1,...
CROSSREFS
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Jun 03 2004
STATUS
approved