[seqfan] Re: A335071 question.

[Neil Sloane]

I just created A335153 (a(1)=0; thereafter a(n) =
(n-1)*sigma(n)-n*sigma(n-1) ),
hoping the graph would show something interesting.  But it doesn't!

Best regards
Neil

Neil J. A. Sloane, President, OEIS Foundation.
11 South Adelaide Avenue, Highland Park, NJ 08904, USA.
Also Visiting Scientist, Math. Dept., Rutgers University, Piscataway, NJ.
Phone: 732 828 6098; home page: http://NeilSloane.com
Email: njasloane at gmail.com



On Sat, May 30, 2020 at 2:21 PM Harvey P. Dale <hpd at hpdale.org> wrote:

> MM:
>
>             There are no two consecutive numbers with the same abundancy
> within the first million numbers.
>            Best,
>            Harvey
>
>
>
> -----Original Message-----
> From: SeqFan <seqfan-bounces at list.seqfan.eu> On Behalf Of
> michel.marcus at free.fr
> Sent: Saturday, May 30, 2020 10:27 AM
> To: Sequence Fanatics Discussion list <seqfan at list.seqfan.eu>
> Subject: [seqfan] A335071 question.
>
>
>
>
>
> Hello Seqfan,
>
>
>
>
>
> In A335071, there is a question: Can two consecutive numbers have the same
> abundancy: sigma(m)/m = sigma(m+1)/(m+1)?
>
> Do you have an idea ?
>
>
>
>
>
> Best.
>
> MM
>
>
>
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