%I M4271 N1785 #25 Dec 27 2017 01:27:16
%S 1,6,60,1368,15552,201240,2016432,21582624,201060768,1944012744,
%T 17257455960,156760071600,1346073913440,11734199738820,98420246759688
%N Number of ways of folding a 3 X n strip of stamps.
%D N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H W. F. Lunnon, <a href="http://dx.doi.org/10.1093/comjnl/14.1.75">Multi-dimensional map-folding</a>, Computer Journal 14 1971 75-80.
%H <a href="/index/Fo#fold">Index entries for sequences obtained by enumerating foldings</a>
%K nonn,more
%O 0,2
%A _N. J. A. Sloane_
%E a(8)-a(14) from _Fred Lunnon_ and _Sean A. Irvine_, Dec 26 2017