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A063965
Size of the automorphism group of the group S_n x S_n (where S_n is the symmetric group).
1
1, 6, 72, 1152, 28800, 4147200, 50803200, 3251404800, 263363788800, 26336378880000, 3186701844480000, 458885065605120000, 77551576087265280000, 15200108913103994880000
OFFSET
1,2
LINKS
FORMULA
Except for n = 1, 2, and 6, a(n) = A048617(n) = 2*(n!)^2.
MAPLE
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:
PROG
(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
CROSSREFS
Sequence in context: A196882 A289392 A272688 * A347023 A362722 A214875
KEYWORD
nonn
AUTHOR
Ahmed Fares (ahmedfares(AT)my-deja.com), Sep 04 2001
EXTENSIONS
More terms from James A. Sellers, Sep 26 2001
STATUS
approved