%I #6 Aug 31 2019 15:48:27
%S 256,9216,215296,6170256,190219264,5771137024,173342326336,
%T 5217149355664,157210070262336,4736078434765584,142657909428672400,
%U 4297207390388366224,129444764469058322064,3899248609061089917504,117456328654788972226816
%N Number of (n+2) X (4+2) 0..3 arrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero.
%C Column 4 of A230977.
%H R. H. Hardin, <a href="/A230973/b230973.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=1
%e ..0..1..0..3..0..1....0..1..0..1..2..3....0..1..0..3..0..3....0..1..2..3..0..1
%e ..2..1..0..3..2..1....0..1..2..3..0..1....0..1..2..3..0..1....2..1..0..3..2..1
%e ..0..3..2..3..2..1....0..3..2..3..2..3....0..1..2..1..2..3....0..3..2..1..2..1
%Y Cf. A230977.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 02 2013
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