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%I #5 Mar 31 2012 12:36:25
%S 1,3,4,19,31,70,117,253,538,1169,2401,4896,10179,21291,44754,93367,
%T 194747,405806,848007,1772209,3704016,7737207,16162351,33766226,
%U 70554991,147429719,308053298,643669403,1344939023,2810299720,5872263661
%N Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 0,2,1,3,4 for x=0,1,2,3,4
%C Every 0 is next to 0 0's, every 1 is next to 1 2's, every 2 is next to 2 1's, every 3 is next to 3 3's, every 4 is next to 4 4's
%C Column 3 of A196138
%H R. H. Hardin, <a href="/A196133/b196133.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = a(n-1) +a(n-2) +a(n-3) +3*a(n-4) +3*a(n-5) +6*a(n-6) -5*a(n-7) -14*a(n-8) -17*a(n-9) -32*a(n-10) -25*a(n-11) -38*a(n-12) -11*a(n-13) +19*a(n-14) +39*a(n-15) +42*a(n-16) +6*a(n-17) +18*a(n-18) +20*a(n-19) +32*a(n-20) +24*a(n-21)
%e Some solutions for n=4
%e ..1..1..2....0..1..2....1..1..2....1..2..1....0..1..2....2..1..1....0..1..2
%e ..2..1..1....2..1..1....2..0..1....1..2..1....1..0..1....1..1..2....1..0..1
%e ..2..1..1....1..1..0....1..1..0....1..2..1....2..1..1....1..1..2....2..2..1
%e ..1..1..2....0..2..1....0..2..1....1..2..1....0..1..2....2..1..1....1..1..0
%K nonn
%O 1,2
%A _R. H. Hardin_ Sep 28 2011
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