%I A087775
%S A087775 1,2,2,1,2,1,1,2,4,1,2,7,1,2,10,1,2,13,1,2,16,1,2,19,1,2,22,1,2,25,1,2,
               28,1,
%T A087775 2,31,1,2,34,1,2,37,1,2,40,1,2,43,1,2,46,1,2,49,1,2,52,1,2,55,1,2,58,1,
               2,61,
%U A087775 1,2,64,1,2,67,1,2,70,1,2,73,1,2,76,1,2,79,1,2,82,1,2,85,1,2,88,1,2,91,
               1,2
%V A087775 1,2,2,1,2,-1,1,2,-4,1,2,-7,1,2,-10,1,2,-13,1,2,-16,1,2,-19,1,2,-22,1,
               2,-25,1,2,-28,1,
%W A087775 2,-31,1,2,-34,1,2,-37,1,2,-40,1,2,-43,1,2,-46,1,2,-49,1,2,-52,1,2,-55,
               1,2,-58,1,2,-61,
%X A087775 1,2,-64,1,2,-67,1,2,-70,1,2,-73,1,2,-76,1,2,-79,1,2,-82,1,2,-85,1,2,-88,
               1,2,-91,1,2
%N A087775 a[1] = 1, a[2] = 2, a[3] = 2; a[n] = 3*a[abs[a[n-2]]] - 3*a[n-abs[a[n-2]]] 
               + a[n-3].
%C A087775 A recursive sequence based on A087774 and the Mallows A005229 sequence. 
               A tick-tock sequence where the form is: 1,2,a(n-3)-3
%t A087775 hg[n_Integer?Positive] := hg[n] =3*hg[Abs[hg[n-2]]] -3*hg[n-Abs[hg[n-2]]]+hg[n-3] 
               hg[1] =1 hg[2] =2 hg[3]=2 digits=200 a=Table[hg[n], {n, 1, digits}]
%Y A087775 Cf. A005229.
%Y A087775 Sequence in context: A088424 A097456 A164002 this_sequence A089955 A046816 
               A138328
%Y A087775 Adjacent sequences: A087772 A087773 A087774 this_sequence A087776 A087777 
               A087778
%K A087775 sign
%O A087775 1,2
%A A087775 Roger L. Bagula (rlbagulatftn(AT)yahoo.com), Oct 04 2003