%I #9 May 23 2014 00:35:25

%S 0,0,8,12,16,20,40,48,62,76,98,116,136,156,188,208

%N Length of the longest directed, closed, non-intersecting rook path on an n X n chessboard avoiding right turns on squares of one color and avoiding left turns on the other color.

%C Turns must be chromatically correct. E.g., n=3, R=Right Turn, A=Ahead, longest path is 8:

%C RAR

%C A A

%C RAR

%H Alex Chernov, <a href="http://alex-black.ru/article.php?content=191">Length of the longest rook path</a>

%K hard,nonn

%O 1,3

%A _David Scambler_, May 12 2009

%E a(10)-a(16) from _Alex Chernov_, Jan 15 2012