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%I #23 Nov 26 2020 16:51:48
%S 11,22,1212,2121,121121,212212,12211221,21122112,122112122112,
%T 211221211221,1221211212212112,2112122121121221,
%U 122121121221122121121221,211212212112211212212112,12212112211212211221211221121221,21121221122121122112122112212112
%N Squares in the Thue-Morse word A001285.
%C A square in an infinite word w is a factor of the form uu, where u has finite length.
%C Consists of 11, 22, 121121, 212212 and their repeated images under the morphism 1 -> 12, 2 -> 21.
%C Replacing {1,2} by {0,1} gives the squares in A010060.
%H James D. Currie and Narad Rampersad, <a href="https://arxiv.org/abs/0803.1189">Infinite words containing squares at every position</a>, arXiv:0803.1189 [math.CO], 2008; or <a href="https://doi.org/10.1051/ita/2010007">also</a>, RAIRO-Theor. Inf. Appl. 44, 113-124 (2010).
%Y Cf. A001285, A020060, A225188 (square roots).
%K nonn
%O 1,1
%A _N. J. A. Sloane_, May 04 2013
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