A197275 - OEIS

%I #5 Mar 31 2012 12:36:29

%S 4,14,34,92,317,888,2626,8078,24103,72107,217970,656610,1975147,

%T 5955136,17950843,54086244,163025795,491430743,1481229421,4464844849,

%U 13458804609,40569450638,122290929298,368632726282,1111201586358,3349591968789

%N Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,1,1,1 for x=0,1,2,3,4

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

%C Column 3 of A197280

%H R. H. Hardin, <a href="/A197275/b197275.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = 3*a(n-1) +a(n-2) -6*a(n-4) -11*a(n-5) +19*a(n-6) -13*a(n-7) -64*a(n-8) +21*a(n-9) +36*a(n-10) -8*a(n-11) -93*a(n-12) +28*a(n-13) -52*a(n-14) -11*a(n-15) +27*a(n-16) -16*a(n-17) -a(n-18) +3*a(n-19)

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Oct 12 2011