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%I #10 Jun 24 2018 21:52:42
%S 1,6,72,1152,28800,4147200,50803200,3251404800,263363788800,
%T 26336378880000,3186701844480000,458885065605120000,
%U 77551576087265280000,15200108913103994880000
%N Size of the automorphism group of the group S_n x S_n (where S_n is the symmetric group).
%H Harry J. Smith, <a href="/A063965/b063965.txt">Table of n, a(n) for n = 1..100</a>
%F Except for n = 1, 2, and 6, a(n) = A048617(n) = 2*(n!)^2.
%p 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 (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) ) } \\ _Harry J. Smith_, Sep 04 2009
%Y Cf. A060249, A048617.
%K nonn
%O 1,2
%A Ahmed Fares (ahmedfares(AT)my-deja.com), Sep 04 2001
%E More terms from _James A. Sellers_, Sep 26 2001