%I A063965
%S A063965 1,6,72,1152,28800,4147200,50803200,3251404800,263363788800,
%T A063965 26336378880000,3186701844480000,458885065605120000,
%U A063965 77551576087265280000,15200108913103994880000
%N A063965 Size of the automorphism group of the group S_n x S_n (where S_n is the
symmetric group ).
%H A063965 Harry J. Smith, <a href="b063965.txt">Table of n, a(n) for n=1,...,100</
a>
%F A063965 Except for n=1, 2, 6 a(n) = A048617(n) = 2 * (n!)^2
%p A063965 a := proc(n) option remember: if n=1 then RETURN(1) fi: if n=2 then RETURN(6)
fi: if n=6 then RETURN(4147200) fi: 2*(n!)^2: end: for n from 1 to
30 do printf(`%d,`,a(n)) od:
%o A063965 (PARI) { for (n=1, 100, if (n==1, a=1, if (n==2, a=6, if (n==6, a=4147200,
a=2*(n!)^2))); write("b063965.txt", n, " ", a) ) } [From Harry J.
Smith (hjsmithh(AT)sbcglobal.net), Sep 04 2009]
%Y A063965 A060249, A048617.
%Y A063965 Sequence in context: A156128 A052678 A052719 this_sequence A047058 A001763
A003235
%Y A063965 Adjacent sequences: A063962 A063963 A063964 this_sequence A063966 A063967
A063968
%K A063965 nonn
%O A063965 1,2
%A A063965 Ahmed Fares (ahmedfares(AT)my-deja.com), Sep 04 2001
%E A063965 More terms from James A. Sellers (sellersj(AT)math.psu.edu), Sep 26 2001
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