%I #5 Mar 31 2012 12:36:34
%S 13,177,1399,14109,146187,1532249,16411255,176845253,1916108803,
%T 20825391089,226732488271,2471217945565,26951222470875,
%U 294040889182217,3208725606852775,35019790320698997,382232607221676979
%N Number of 2nX4 0..2 arrays with values 0..2 introduced in row major order and each element unequal to exactly two horizontal and vertical neighbors
%C Column 2 of A198452
%H R. H. Hardin, <a href="/A198448/b198448.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 20*a(n-1) -94*a(n-2) -208*a(n-3) +1351*a(n-4) +5600*a(n-5) -22336*a(n-6) -39628*a(n-7) +116496*a(n-8) +216496*a(n-9) -188416*a(n-10) -809920*a(n-11) -267264*a(n-12) +1638400*a(n-13)
%e Some solutions for n=3
%e ..0..1..1..0....0..1..1..0....0..1..1..0....0..1..2..0....0..1..2..0
%e ..1..2..2..1....2..2..2..2....2..2..2..2....1..1..2..2....2..1..2..2
%e ..1..2..2..1....0..0..0..0....0..0..0..0....0..0..0..0....2..1..0..0
%e ..2..1..1..0....2..2..2..1....1..2..2..1....2..1..1..2....1..1..0..1
%e ..2..1..1..0....0..0..2..1....1..2..2..1....2..1..1..2....0..0..0..1
%e ..0..2..2..1....1..0..2..0....0..1..1..2....1..2..2..1....1..2..2..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Oct 25 2011
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