[seqfan] Re: Sigma_2

[Frank Adams-Watters]

While we're at it, is A232681 the complement of A031363?

Franklin T. Adams-Watters


-----Original Message-----
From: Don Reble <djr at nk.ca>
To: Sequence Fanatics Discussion list <seqfan at list.seqfan.eu>
Sent: Tue, Mar 29, 2016 8:35 am
Subject: [seqfan] Re: Sigma_2

> Is A031363 the set of all numbers n such that sigma_2(n) is not> divisible by 5? If not, where is the first difference?    11^4.    The first few differences are multiples of p^4,    where p is in {11, 19, 29, 31, 41}.    Those might be the primes == 1 or 4 mod 5 (almost A038872).-- Don Reble  djr at nk.ca--Seqfan Mailing list - http://list.seqfan.eu/