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%I #11 Dec 14 2014 16:23:33
%S 91,1693,42874,1181303,33787978,986306398,29202473260,873679701315,
%T 26348265181700,799618906955872,24390561043319626,747104810403124190,
%U 22965144760897452728,708038892975800125716,21885932074900784746650
%N Half the number of (n+1) X 5 binary arrays with equal numbers of majority one 2 X 2 subblocks and majority zero 2 X 2 subblocks.
%C Column 4 of A184467.
%H R. H. Hardin, <a href="/A184462/b184462.txt">Table of n, a(n) for n = 1..187</a>
%e Some solutions for 3 X 5:
%e ..0..1..0..0..0....0..1..1..0..0....0..0..0..0..0....0..0..0..1..0
%e ..0..1..1..0..1....1..1..0..1..0....1..0..1..1..0....0..0..1..1..1
%e ..0..1..1..0..1....0..0..0..1..0....1..1..1..0..1....0..0..0..1..1
%e ...
%e ...E..P..M..M.......P..P..E..M.......M..M..E..M.......M..M..P..P...
%e ...E..P..E..E.......E..M..E..E.......P..P..P..E.......M..M..P..P...
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 15 2011