%I #6 Dec 28 2023 19:35:15
%S 1,2,2,15,41,716,2847,83440,426422,18171918,112072316,6423127757,
%T 46054057965,3376465219485,27457462735926,2486327138729353,
%U 22530435476364494,2454996141671330713,24463971326544703312
%N Number of horizontal, diagonal and antidiagonal neighbor colorings of the odd squares of a 3 X n array with new integer colors introduced in row major order.
%C Row 3 of A216612.
%H R. H. Hardin, <a href="/A216613/b216613.txt">Table of n, a(n) for n = 1..41</a>
%e Some solutions for n=4
%e ..x..0..x..1....x..0..x..1....x..0..x..1....x..0..x..1....x..0..x..1
%e ..2..x..3..x....2..x..3..x....1..x..2..x....2..x..3..x....2..x..3..x
%e ..x..0..x..4....x..4..x..5....x..0..x..3....x..4..x..1....x..1..x..0
%Y Cf. A216612.
%K nonn
%O 1,2
%A _R. H. Hardin_, Sep 10 2012