%I M1904 #19 Apr 30 2020 21:40:22

%S 2,8,112,5856,869824

%N Reachable configurations on n circles.

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%H Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a005/A005787.java">Java program</a> (github)

%H D. Rubinstein, Jeffrey Shallit and M. Szegedy, <a href="http://dx.doi.org/10.1145/63039.63046">A subset coloring algorithm and its application to computer graphics</a>, Commun. ACM, 31 (1988), 1228-1232.

%K nonn,nice,hard,more

%O 1,1

%A _N. J. A. Sloane_, _Jeffrey Shallit_

%E a(5) from _Sean A. Irvine_, Apr 30 2020