A197643 - OEIS

%I #5 Mar 31 2012 12:36:30

%S 1,11,82,342,1649,9007,49381,256485,1303838,6775152,35730226,

%T 187160271,972480937,5058363340,26414032504,137991741860,719704308772,

%U 3751431869467,19565984801032,102090380933252,532589325917487

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

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

%C Column 3 of A197648

%H R. H. Hardin, <a href="/A197643/b197643.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n) = 3*a(n-1) +22*a(n-3) +162*a(n-4) +207*a(n-5) +40*a(n-6) -199*a(n-7) -964*a(n-8) -1725*a(n-9) -4618*a(n-10) +565*a(n-11) +1265*a(n-12) +854*a(n-13) -504*a(n-14) +24*a(n-15)

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,2

%A _R. H. Hardin_ Oct 16 2011