Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #12 Dec 20 2015 17:11:55
%S 1,2,5,52,203,4140,21147,678570,4213597,190899322,1382958545,
%T 82864869804,682076806159,51724158235372,474869816156751,
%U 44152005855084346,445958869294805289,49631246523618756274,545717047936059989389
%N Number of horizontal and antidiagonal neighbor colorings of the odd squares of an n X 3 array with new integer colors introduced in row major order.
%C Column 3 of A216084.
%C Appears to be identical to A000110 except for elements in the latter indexed by 3x + 2 for x >= 0. - _Chris Boyd_, Dec 20 2015
%H R. H. Hardin, <a href="/A216079/b216079.txt">Table of n, a(n) for n = 1..210</a>
%e Some solutions for n=4:
%e ..x..0..x....x..0..x....x..0..x....x..0..x....x..0..x....x..0..x....x..0..x
%e ..1..x..0....1..x..2....1..x..2....1..x..2....1..x..0....1..x..0....1..x..0
%e ..x..2..x....x..3..x....x..0..x....x..0..x....x..1..x....x..1..x....x..2..x
%e ..3..x..2....4..x..3....3..x..0....2..x..0....2..x..3....2..x..1....3..x..0
%K nonn
%O 1,2
%A _R. H. Hardin_, Sep 01 2012