[seqfan] Re: Two branches in scatter graph of A102605

Hugo Pfoertner yae9911 at gmail.com
Fri Oct 27 06:16:46 CEST 2017


Harald Helfgott's article cited in https://oeis.org/A054860
Major arcs for Goldbach's problem <https://arxiv.org/abs/1305.2897>
might provide a method to determine the boundaries of the branches, but
that is tough stuff (at least for me).

BTW, I don't see any reason for the "base" keyword in A102605.

Hugo Pfoertner

On Fri, Oct 27, 2017 at 3:58 AM, Neil Sloane <njasloane at gmail.com> wrote:

> Zak,  That is a very interesting question
>
> To see the graph, the URL should be https://oeis.org/A102605/graph.
>
> One thing we might try is to define two new sequences, A; n such that
> a(n) is on the lower branch;   B, n such that a(n) is on the upper branch
>
> Here is a piece of the b-file:
> ...
> 123 125
> 124 91
> 125 135
> 126 128
> 127 89
> 128 143
> 129 127
> 130 94
> 131 146
> 132 127
> 133 102
> 134 147
> 135 141
> 136 105
>
>
> so A contains ..., 124, 127, 130, 133, 136, ...
>
> and B contains ..., 123, 125, 126, 128, 129, 131, 132(?), 134, ...
>
>
> One could then work backwards to get the beginning of the two
> sequence, and forwards to get more terms,
>
> and we might get at the least 2 new sequences. Or they might be
> sequences that are in the OEIS!
>
>
>
>
> 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 Thu, Oct 26, 2017 at 6:51 PM, zak seidov via SeqFan <
> seqfan at list.seqfan.eu> wrote:
>
> > Any explanation of two "branches in" scatter graph of A102605?
> >  https://oeis.org/A102605/graphA102605 Number of ways of writing 2n+1 as
> > p+q+r where p,q,r are primes with p < q < r.Thx,Zak
> >
> >
> > --
> > Seqfan Mailing list - http://list.seqfan.eu/
> >
>
> --
> Seqfan Mailing list - http://list.seqfan.eu/
>


More information about the SeqFan mailing list