%I #5 Mar 31 2012 12:36:27
%S 1,7,71,401,2975,20191,141833,986015,6866117,47832829,333044999,
%T 2319651781,16154076631,112501830469,783493377407,5456430897109,
%U 38000064950619,264641895220837,1843034804766363,12835364615219383
%N Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,3,1,0,2 for x=0,1,2,3,4
%C Every 0 is next to 0 4's, every 1 is next to 1 3's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 2's
%C Column 4 of A196904
%H R. H. Hardin, <a href="/A196900/b196900.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 4*a(n-1) +29*a(n-2) -30*a(n-3) -227*a(n-4) +183*a(n-5) +345*a(n-6) -1223*a(n-7) +1953*a(n-8) +1175*a(n-9) -3050*a(n-10) +1433*a(n-11) +1011*a(n-12) -2381*a(n-13) -297*a(n-14) +1000*a(n-15) +282*a(n-16) -176*a(n-17) -85*a(n-18) +20*a(n-19) +6*a(n-20) -a(n-21)
%e Some solutions for n=5
%e ..0..0..0..0....0..3..0..0....0..0..3..0....0..0..3..0....0..0..0..0
%e ..0..0..1..0....0..0..0..0....0..1..0..0....1..3..0..3....3..0..0..3
%e ..3..0..3..0....0..0..0..0....0..3..0..0....0..0..0..0....0..3..1..0
%e ..0..3..0..3....0..0..0..0....3..0..0..0....3..0..0..3....0..0..0..0
%e ..0..1..0..0....0..0..0..0....0..0..3..0....0..0..3..0....0..0..3..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Oct 07 2011
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