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A181949
Weighted sum of all cyclic subgroups of the Symmetric Group.
2
1, 3, 10, 43, 231, 1531, 11068, 89895, 820543, 8484871, 95647476, 1186289083, 15648402355, 221728356123, 3354790995676, 53999879550991, 936289020367263, 17163114699673615, 328827078340587148, 6630244432204704771, 139769193881466850051, 3092293682224076627683
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
a(n) = Sum_{k=1..A000793(n)} k*A074881(n, k). - Andrew Howroyd, Jul 02 2018
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