OFFSET
1,2
COMMENTS
Sum of the orders of all cyclic subgroups of the Sym_n.
The identity permutation is counted for each subgroup, i.e. A051625(n) times.
Each permutation is counted several times according to its conjugacy class.
FORMULA
EXAMPLE
a(4) = 1*1 + 2*3 + 2*6 + 3*4 + 4*3 = 1+6+12+12+12 = 43.
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Olivier Gérard, Apr 03 2012
EXTENSIONS
a(9)-a(22) from Andrew Howroyd, Jul 02 2018
STATUS
approved