%I A121386
%S A121386 2,4,6,10,14,20,16,6,36,8,44,10,8,30,16,8,12,2,12,28,64,110,96,134,56,
%T A121386 44,16,2,16,74,116,188,200,180
%N A121386 Number of different colorings of {1,...,n} that minimize the number of 
               three-term arithmetic progressions that such a coloring can contain.
%C A121386 The unique (up to switching colors) sequences for n=18 and n=28 are 001001111000011011 
               and 0001100011111100000011100111 respectively.
%e A121386 a(3)=6 because all non-monochromatic colorings are such an example
%Y A121386 Cf. A121385.
%Y A121386 Sequence in context: A024204 A036641 A062425 this_sequence A007777 A082379 
               A167379
%Y A121386 Adjacent sequences: A121383 A121384 A121385 this_sequence A121387 A121388 
               A121389
%K A121386 nonn
%O A121386 1,1
%A A121386 Steve Butler (sbutler(AT)math.ucsd.edu), Jul 26 2006