login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A225186 Squares in the Thue-Morse word A001285. 3
11, 22, 1212, 2121, 121121, 212212, 12211221, 21122112, 122112122112, 211221211221, 1221211212212112, 2112122121121221, 122121121221122121121221, 211212212112211212212112, 12212112211212211221211221121221, 21121221122121122112122112212112 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

A square in an infinite word w is a factor of the form uu, where u has finite length.

Consists of 11, 22, 121121, 212212 and their repeated images under the morphism 1 -> 12, 2 -> 21.

Replacing {1,2} by {0,1} gives the squares in A010060.

REFERENCES

James D. Currie and Narad Rampersad, Infinite words containing squares at every position, RAIRO-Theor. Inf. Appl. 44, 113-124 (2010).

LINKS

Table of n, a(n) for n=1..16.

CROSSREFS

Cf. A001285, A020060, A225188 (square roots).

Sequence in context: A094620 A077431 A118133 * A155973 A253684 A180481

Adjacent sequences:  A225183 A225184 A225185 * A225187 A225188 A225189

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, May 04 2013

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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified November 20 06:06 EST 2018. Contains 317385 sequences. (Running on oeis4.)