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%I #5 Mar 31 2012 12:36:00
%S 234,600,1591,4517,16029,58413,216477,930657,3947025,16260821,
%T 75637161,341430753,1469964069,7087591425,32968435401,145042964117,
%U 711996798489,3363303213633,14962011182037,74119134136017,352902194702745
%N 1/36 the number of (n+2)X4 0..2 arrays with each 3X3 subblock containing two of one value, two of another, and five of the last
%C Column 2 of A184457
%H R. H. Hardin, <a href="/A184450/b184450.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n)=6*a(n-1)-11*a(n-2)+195*a(n-3)-1134*a(n-4)+2079*a(n-5)-11600*a(n-6)+62796*a(n-7)-115126*a(n-8)+263520*a(n-9)-1204344*a(n-10)+2207964*a(n-11)-2907648*a(n-12)+10219824*a(n-13)-18736344*a(n-14)+17243280*a(n-15)-42140736*a(n-16)+77258016*a(n-17)-55857600*a(n-18)+82301184*a(n-19)-150885504*a(n-20)+92378880*a(n-21)-60466176*a(n-22)+110854656*a(n-23)-60466176*a(n-24)
%e Some solutions with a(1,1)=0 for 6X4
%e ..0..0..0..0....0..0..1..2....0..1..0..0....0..0..0..0....0..0..0..0
%e ..0..2..1..0....2..2..1..0....0..2..1..0....2..1..0..2....1..2..0..1
%e ..1..0..2..1....2..2..2..2....0..0..2..0....2..0..1..2....0..2..1..0
%e ..0..0..0..0....0..1..0..2....0..1..0..0....0..0..0..0....2..2..2..2
%e ..0..2..1..0....2..1..2..0....0..1..2..0....0..1..2..0....1..2..0..1
%e ..0..1..2..0....1..1..1..1....2..0..0..2....1..2..0..1....2..1..0..2
%K nonn
%O 1,1
%A _R. H. Hardin_ Jan 14 2011