|
|
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
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
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
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Ahmed Fares (ahmedfares(AT)my-deja.com), Sep 04 2001
|
|
EXTENSIONS
|
|
|
STATUS
|
approved
|
|
|
|