|
%I #7 Feb 21 2023 16:06:27
%S 2,10,31,84,290,923,2887,9216,29288,92868,294893,936361,2972409,
%T 9436595,29959267,95112260,301956214,958634094,3043413512,9662045566,
%U 30674490204,97383543481,309167462063,981526438497,3116091639355,9892781977749
%N Number of nX3 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 3,3,0,2,2 for x=0,1,2,3,4
%C Every 0 is next to 0 3's, every 1 is next to 1 3's, every 2 is next to 2 0's, every 3 is next to 3 2's, every 4 is next to 4 2's
%C Column 3 of A197457
%H R. H. Hardin, <a href="/A197452/b197452.txt">Table of n, a(n) for n = 1..200</a>
%F Empirical: a(n) = 2*a(n-1) +4*a(n-2) +3*a(n-3) -7*a(n-4) -18*a(n-5) -5*a(n-6) +18*a(n-7) +31*a(n-8) +20*a(n-9) -5*a(n-10) -25*a(n-11) -18*a(n-12) -7*a(n-13) +3*a(n-14) +2*a(n-15)
%e Some solutions for n=4
%e ..2..0..2....0..2..0....2..0..0....0..2..0....0..0..0....0..0..2....0..0..2
%e ..0..1..0....2..3..2....0..0..0....0..2..0....0..0..0....0..0..0....0..1..0
%e ..2..3..2....0..1..0....2..2..2....0..2..2....2..2..0....2..2..2....2..3..2
%e ..0..2..0....0..0..2....0..0..0....2..0..0....0..2..0....0..0..0....0..2..0
%K nonn
%O 1,1
%A _R. H. Hardin_ Oct 15 2011
|
