A230897 - OEIS

%I #4 Oct 31 2013 14:43:22

%S 0,70,810,23884,579218,15392914,400106488,10548244824,276988116562,

%T 7290773137370,191799500354366,5047559049038998,132829499753935500,

%U 3495691177600683788,91996653229110438308,2421116272663216851440

%N Number of nX6 0..3 arrays x(i,j) with each element horizontally or vertically next to at least one element with value (x(i,j)+1) mod 4 and at least one element with value (x(i,j)-1) mod 4, no adjacent elements equal, and upper left element zero

%C Column 6 of A230899

%H R. H. Hardin, <a href="/A230897/b230897.txt">Table of n, a(n) for n = 1..210</a>

%e Some solutions for n=4

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

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

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

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

%K nonn

%O 1,2

%A _R. H. Hardin_, Oct 31 2013