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%I #9 Apr 09 2018 09:53:14
%S 153,155,158,164,174,194,230,302,438,710,1238,2294,4374,8534,16790,
%T 33302,66198,131990,263318,525974,1050774,2100374,4198550,8394902,
%U 16785558,33566870,67125398,134242454,268468374,536920214,1073807510,2147582102
%N 1/4 the number of (n+1) X 9 binary arrays with all 2 X 2 subblock sums the same.
%C Column 8 of A183986.
%H R. H. Hardin, <a href="/A183985/b183985.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 3*a(n-1) - 6*a(n-3) + 4*a(n-4).
%F Conjectures from _Colin Barker_, Apr 09 2018: (Start)
%F G.f.: x*(153 - 304*x - 307*x^2 + 608*x^3) / ((1 - x)*(1 - 2*x)*(1 - 2*x^2)).
%F a(n) = 3*2^(n/2-1) + 2^(n-1) + 150 for n even.
%F a(n) = 2^(n-1) + 2^((n+1)/2) + 150 for n odd.
%F (End)
%e Some solutions for 5 X 9:
%e ..0..0..1..1..1..0..0..1..1....0..1..0..0..1..1..1..1..1
%e ..1..1..0..0..0..1..1..0..0....1..0..1..1..0..0..0..0..0
%e ..0..0..1..1..1..0..0..1..1....0..1..0..0..1..1..1..1..1
%e ..1..1..0..0..0..1..1..0..0....1..0..1..1..0..0..0..0..0
%e ..0..0..1..1..1..0..0..1..1....0..1..0..0..1..1..1..1..1
%Y Cf. A183986.
%K nonn
%O 1,1
%A _R. H. Hardin_, Jan 08 2011
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