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%I #12 Jun 09 2015 14:15:11
%S 1,1,8,336,64512,53329920,184308203520,2621599886868480,
%T 152122702768688332800,35820150273699719298416640,
%U 34112245508649716682268134604800,131089993748184007771243790830298726400,2029650642403883210241235064170615545004032000
%N Order of general affine group AGL(n,2) (=A028365(n)) divided by (n+1).
%H Max Alekseyev, <a href="/A258745/b258745.txt">Table of n, a(n) for n = 0..100</a>
%H <a href="http://math.ucsd.edu/~pfitz/downloads/putnam/putnam1999.pdf">Putnam Exam. 1999</a>, Question A6, Amer. Math. Monthly 107 (Oct 2000), 721-732; see p. 725.
%F a(n) = A028365(n) / (n+1) = 2^n * A002884(n) / (n+1) = 2^n * n! * A053601(n) / (n+1).
%K nonn
%O 0,3
%A _Max Alekseyev_, Jun 08 2015