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%I #4 Dec 25 2017 12:33:25
%S 1,1,0,1,0,-1,1,1,0,-1,1,0,-1,1,0,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,
%T 1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,
%U -1,1,0,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0,-1,1,0
%N Simple quasi-periodic sequence consisting of the terms 1, 0 and -1.
%H A. Karttunen, <a href="http://www.iki.fi/~kartturi/matikka/stebrota.htm">Conjecture regarding A065249 and A065251</a>
%F a(n) = 1-((n-2^[log_2(n)]) mod 3)
%p [seq(A065251(j),j=1..120)]; A065251 := n -> 1-((n-2^floor_log_2(n)) mod 3);
%t Table[1-Mod[n-2^Floor[Log[2,n]],3],{n,110}] (* _Harvey P. Dale_, Dec 25 2017 *)
%Y The same sequence modulo 3: A065252. Cf. A065249.
%K sign
%O 1,1
%A _Antti Karttunen_, Oct 25 2001