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%I #9 Oct 16 2014 04:26:27
%S 0,0,0,1,0,0,1,0,0,0,1,1,1,2,0,0,0,1,0,1,1,1,2,2,2,0,0,2,0,0,0,1,1,0,
%T 1,1,0,1,1,1,2,2,1,2,1,2,2,4,0,0,0,2,0,0,2,0,0,0,1,1,1,2,0,1,0,0,0,1,
%U 1,1,2,3,1,2,1,1,1,2,2,0,2,2,2,4,4,3,0,0,0,2,0,1,2,0,4,2,1,5,0,2,1,1,2,1,0,0,2,2,0,0,0,3,0,0,1,1,1,4,1,2,3,0,1,2,1,0,3,3,4,1,1,3
%N Least nonnegative sequence which does not contain a 4-term equidistant subsequence (a(n+k*d); k=0,1,2,3) in arithmetic progression.
%C See A248625 for more information, links and examples.
%C See A248641 for the "positive integers" variant.
%o (PARI) a=[];for(n=1,190,a=concat(a,0);while(hasAP(a,4),a[#a]++));a \\ See A248625 for hasAP().
%Y Cf. A248625, A248640, A248641, A248627, A229037, A241752.
%K nonn
%O 0,14
%A _M. F. Hasler_, Oct 10 2014