[seqfan] Re: Puzzle sequence A288573

Neil Sloane njasloane at gmail.com
Thu Jun 29 04:48:17 CEST 2017


Frank,  Your explanation rings true. But since
it is not an exact match, could you create an entry for your sequence and
tell me the A-number?  Then I will change the description of A288753 to say
that it is most likely an erroneous version of ...

Incidentally, my posting to the OEIS Facebook page about that sequence has
received exactly one comment so far, which appears to consist of a video of
a person picking his nose.
This was my first posting to Facebook for several years, and will probably
be my last.


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 Wed, Jun 28, 2017 at 10:17 PM, Frank Adams-Watters via SeqFan <
seqfan at list.seqfan.eu> wrote:

> I can almost duplicate this
>
> The total of the number of distinct primes in each representation of 2*n+1
> as a sum of 3 primes.  I.e., a representation as p+p+p counts as 1, as
> p+p+q counts as 2, and p+q+r counts as 3.
>
> This differs from the entered numbers at 2*n+1 = 25 (I get 12, entered as
> 11), and the final three values: I get 41,41,45 instead of 40,43,43.
>
> Here's a PARI program. The n input to this program is the 2*n+1 in the
> sequence definition.
>
> a(n)=my(p,q,r,cnt);forprime(p=3,n\3,forprime(q=p,(n-p)\2,if(
> isprime(r=n-p-q),cnt+=if(p===q&&p==r,1,if(p==q||q==r,2,3)))));cnt
>
> So there are two possibilities: (1) I may have found the original
> definition, but there are some errors, or (2) my matching values are a
> coincidence. Possibility (1) is the sort of thing you would expect to see
> if the values were hand-computed.
>
> Franklin T. Adams-Watters
>
>
> -----Original Message-----
> From: Neil Sloane <njasloane at gmail.com>
> To: Sequence Fanatics Discussion list <seqfan at list.seqfan.eu>
> Sent: Wed, Jun 28, 2017 11:35 am
> Subject: [seqfan] Puzzle sequence A288573
>
> I just created A288573 for a sequence whose definition is not clear to me.
> Someone was asking me why I never post anything to the OEIS page on
> Facebook, so as an experiment I just posted a more detailed version of this
> question there.
>
> The Kashihara booklet where I found this sequence has a lot of other
> sequences that may or may not be in the OEIS.
>
> You can see the booklet in A288573.
>
> --Seqfan Mailing list - http://list.seqfan.eu/
>
> --
> Seqfan Mailing list - http://list.seqfan.eu/
>



More information about the SeqFan mailing list