A197085 - OEIS

%I #5 Mar 31 2012 12:36:28

%S 1,5,25,96,422,1780,7537,31911,135283,573054,2427879,10286742,

%T 43582082,184647156,782310778,3314472134,14042671183,59495654829,

%U 252069704002,1067962669281,4524717892087,19170212756069,81219883046173

%N Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,3,2,0,1 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 2's, every 3 is next to 3 0's, every 4 is next to 4 1's

%C Column 3 of A197090

%H R. H. Hardin, <a href="/A197085/b197085.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = 3*a(n-1) +3*a(n-2) +10*a(n-3) -3*a(n-4) +2*a(n-5) +11*a(n-6) -15*a(n-7) -15*a(n-8) -2*a(n-9) +a(n-10) -2*a(n-11) +4*a(n-12) +2*a(n-13)

%e Some solutions for n=4

%e ..0..3..0....0..1..0....0..3..0....2..2..2....0..0..0....0..3..0....0..0..0

%e ..0..0..0....0..3..0....3..0..3....2..0..2....0..0..0....0..0..3....0..0..0

%e ..0..0..3....0..0..0....0..0..0....2..0..2....0..0..3....2..2..0....3..0..0

%e ..0..3..0....0..3..0....0..3..0....2..2..2....0..3..0....2..2..0....0..3..0

%K nonn

%O 1,2

%A _R. H. Hardin_ Oct 10 2011