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A181955
Weighted sum of all cyclic subgroups of prime order in the Alternating group.
3
0, 0, 3, 18, 90, 390, 2205, 10878, 45318, 256350, 5530305, 55869330, 865551258, 9892489698, 78223384785, 470010394350, 24530527675230, 409760923017198, 10595007772540113, 160826214447439770, 1585844008081570650, 16787211082925012730, 1362379219330719093273
OFFSET
1,3
COMMENTS
Sum of p for all p-subgroups in Alt_n.
LINKS
FORMULA
a(n) = A181954(n) - 2*A001465(n). - Andrew Howroyd, Jul 03 2018
PROG
(PARI) a(n)={sum(p=2, n, if(isprime(p), sum(k=1, n\p, if(p>2||k%2==0, n!/(k!*(n-k*p)!*p^k)))*p/(p-1)))} \\ Andrew Howroyd, Jul 03 2018
CROSSREFS
Cf. A181951 (number of such subgroups).
Cf. A181954 (symmetric case).
Cf. A001465.
Sequence in context: A290331 A124811 A006568 * A147518 A088336 A133594
KEYWORD
nonn
AUTHOR
Olivier Gérard, Apr 03 2012
EXTENSIONS
Terms a(9) and beyond from Andrew Howroyd, Jul 03 2018
STATUS
approved