%I
%S 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 44,16,2,16,74,116,188,200,180
%N Number of different twocolorings of {1,...,n} that minimize the number of monochromatic threeterm arithmetic progressions that such a coloring can contain.
%C The unique (up to switching colors) sequences for n=18 and n=28 are 001001111000011011 and 0001100011111100000011100111 respectively.
%e a(3)=6 because all nonmonochromatic colorings are such an example
%Y Cf. A005346, A121385.
%K nonn
%O 1,1
%A _Steve Butler_, Jul 26 2006
%E Definition corrected by _Rob Pratt_, Jun 11 2014
