%I #7 May 03 2021 15:06:18
%S 15,887,39321,1704619,74665511,3271362341,143280358783,6275473692531,
%T 274859698649841,12038586622802263,527278170826443931,
%U 23094261763297231417,1011505808556752689163,44302953319140331180267
%N Number of n X 4 0..2 arrays with every 0 next to a 1 and every 1 next to a 2 horizontally or vertically.
%C Column 4 of A232368.
%H R. H. Hardin, <a href="/A232364/b232364.txt">Table of n, a(n) for n = 1..210</a>
%H R. H. Hardin, <a href="/A232364/a232364.txt">Empirical recurrence of order 60</a>
%F Empirical recurrence of order 60 (see link above)
%e Some solutions for n=3
%e ..1..2..2..2....2..2..0..1....1..2..1..2....0..1..2..2....1..0..1..2
%e ..0..2..1..0....1..1..2..2....2..1..1..2....1..0..1..2....2..2..2..2
%e ..2..1..1..2....2..1..0..1....1..0..0..1....2..2..2..2....2..0..1..2
%Y Cf. A232368.
%K nonn
%O 1,1
%A _R. H. Hardin_, Nov 23 2013