%I #6 Mar 31 2012 12:36:02
%S 0,171,361,3645,13365,94905,424845,2682129,13079349,78537465,
%T 399963789,2339595729,12218349285,70347244905,373332026493,
%U 2126782533537,11410731148437,64515747347865,348826307822253,1961330707376721
%N Number of (n+1)X2 0..2 arrays with every 2X2 subblock sum equal to some horizontal or vertical neighbor 2X2 subblock sum
%C Column 1 of A185614
%H R. H. Hardin, <a href="/A185610/b185610.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n)=6*a(n-1)+18*a(n-2)-159*a(n-3)+338*a(n-4)-48*a(n-5)-3888*a(n-6)+11346*a(n-7)-26856*a(n-8)+39504*a(n-9)+24264*a(n-10)-101520*a(n-11)+746208*a(n-12)-1142208*a(n-13)+3229632*a(n-14)-3297024*a(n-15)+5474304*a(n-16)-2985984*a(n-17)+2985984*a(n-18)
%e Some solutions for 3X2
%e ..0..1....0..1....1..0....0..2....1..2....0..1....1..2....0..2....0..2....0..1
%e ..1..0....1..2....2..0....1..1....0..0....1..1....1..0....1..0....0..2....0..2
%e ..1..0....0..1....0..1....2..0....1..2....1..0....2..1....0..2....1..1....0..1
%K nonn
%O 1,2
%A _R. H. Hardin_ Jan 31 2011