A196953 - OEIS

%I #5 Mar 31 2012 12:36:27

%S 4,20,87,492,2687,14509,78717,427700,2320738,12593583,68356288,

%T 370995901,2013496775,10928042781,59310677884,321900611044,

%U 1747074166413,9482023129916,51462457739671,279305865035645,1515896714830837

%N Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,1,3,4,0 for x=0,1,2,3,4

%C Every 0 is next to 0 2's, every 1 is next to 1 1's, every 2 is next to 2 3's, every 3 is next to 3 4's, every 4 is next to 4 0's

%C Column 4 of A196957

%H R. H. Hardin, <a href="/A196953/b196953.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 2*a(n-1) +10*a(n-2) +37*a(n-3) +54*a(n-4) -39*a(n-6) -10*a(n-7) -37*a(n-8) -49*a(n-9) -18*a(n-10) -9*a(n-11) -16*a(n-12) +6*a(n-13) -a(n-14) +a(n-15) for n>16

%e Some solutions for n=5

%e ..0..0..0..0....0..0..1..1....0..0..1..1....0..0..0..0....0..0..1..1

%e ..0..0..0..0....0..1..0..0....1..0..0..0....1..0..0..0....0..0..0..0

%e ..0..4..0..0....0..1..0..0....1..0..1..1....1..0..4..0....0..4..0..0

%e ..0..0..1..0....0..0..0..1....0..0..0..0....0..0..0..1....0..0..0..0

%e ..0..0..1..0....0..0..0..1....0..0..1..1....0..0..0..1....1..1..0..0

%K nonn

%O 1,1

%A _R. H. Hardin_ Oct 08 2011