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Weighted sum of all cyclic subgroups of prime order in the Alternating group.
3

%I #15 Jul 03 2018 16:57:27

%S 0,0,3,18,90,390,2205,10878,45318,256350,5530305,55869330,865551258,

%T 9892489698,78223384785,470010394350,24530527675230,409760923017198,

%U 10595007772540113,160826214447439770,1585844008081570650,16787211082925012730,1362379219330719093273

%N Weighted sum of all cyclic subgroups of prime order in the Alternating group.

%C Sum of p for all p-subgroups in Alt_n.

%H Andrew Howroyd, <a href="/A181955/b181955.txt">Table of n, a(n) for n = 1..200</a>

%F a(n) = A181954(n) - 2*A001465(n). - _Andrew Howroyd_, Jul 03 2018

%o (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

%Y Cf. A181951 (number of such subgroups).

%Y Cf. A181954 (symmetric case).

%Y Cf. A001465.

%K nonn

%O 1,3

%A _Olivier Gérard_, Apr 03 2012

%E Terms a(9) and beyond from _Andrew Howroyd_, Jul 03 2018