%I #5 Mar 31 2012 12:35:51

%S 4,28,111,550,2769,13338,66012,326010,1605094,7924940,39109123,

%T 192971113,952409721,4700295351,23196736485,114482463703,564998794109,

%U 2788411309415,13761538059788,67916728397389,335186625133799

%N Number of nX4 binary arrays with every element equal to either the sum mod 2 of its vertical neighbors or the sum mod 2 of its horizontal neighbors

%C Column 4 of A183474

%H R. H. Hardin, <a href="/A183469/b183469.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n)=4*a(n-1)+2*a(n-2)+43*a(n-3)-120*a(n-4)-28*a(n-5)-843*a(n-6)+1176*a(n-7)-295*a(n-8)+8176*a(n-9)-4388*a(n-10)+7759*a(n-11)-37223*a(n-12)+7835*a(n-13)-46292*a(n-14)+89188*a(n-15)-10524*a(n-16)+120676*a(n-17)-118801*a(n-18)+2332*a(n-19)-165492*a(n-20)+73493*a(n-21)+32085*a(n-22)+126221*a(n-23)+24117*a(n-24)-42421*a(n-25)-43901*a(n-26)-35527*a(n-27)+9272*a(n-28)+9759*a(n-29)-9458*a(n-30)+2573*a(n-31)-11427*a(n-32)+1448*a(n-33)+2224*a(n-34)-2291*a(n-35)+1897*a(n-36)-661*a(n-37)-27*a(n-38)+297*a(n-39)+27*a(n-40)-66*a(n-41)+3*a(n-42)-15*a(n-43)-2*a(n-44)+4*a(n-45)

%e Some solutions for 6X4

%e ..1..1..0..1....0..0..1..1....1..1..0..1....1..1..0..0....0..0..0..0

%e ..0..0..1..1....0..0..1..1....0..0..0..1....1..1..0..0....0..0..0..0

%e ..1..1..0..1....0..0..1..1....0..0..0..0....1..1..0..1....0..1..1..0

%e ..0..1..0..0....0..0..1..1....0..1..1..1....1..1..1..1....0..0..0..0

%e ..1..0..0..0....0..0..1..1....0..0..1..1....1..0..1..1....1..0..0..1

%e ..1..1..0..0....0..0..0..0....0..1..1..1....0..0..1..1....1..0..0..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 05 2011