Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #5 Jan 17 2021 16:42:46
%S 0,2,0,1,0,2,3,2,0,2,0,1,3,1,0,1,0,2,0,1,0,2,3,2,3,1,3,2,0,2,3,2,0,2,
%T 0,1,0,2,3,2,0,2,0,1,3,1,0,1,3,1,3,2,3,1,0,1,0,2,0,1,3,1,0,1,0,2,0,1,
%U 0,2,3,2,0,2,0,1,3,1,0,1,0,2,0,1,0,2,3,2,3,1,3,2,0,2,3,2,3,1,3,2,3,1,0,1,3
%N Fixed under 0 -> 02, 1 -> 32, 2 -> 01, 3 -> 31.
%C Yet another version of the Rudin-Shapiro sequence A020987.
%D Dekking, Michel, Michel Mendes France, and Alf van der Poorten. "Folds." The Mathematical Intelligencer, 4.3 (1982): 130-138 & front cover, and 4:4 (1982): 173-181 (printed in two parts). See Observation 1.7.
%Y Cf. A020985, A020987, A100260, A340504.
%K nonn
%O 1,2
%A _N. J. A. Sloane_, Jan 17 2021