[seqfan] Re: Planar distributive lattices

[Neil Sloane]

Allan Wechsler said, in connection with the sequence I created (A343161)
based on Peter Jipsen's enumeration:  "I think writing to him is a great
idea; get him to author that sequence, which he only deserves, after all."
Well, he has been a registered user - and  contributor - to the OEIS since
March 2013.  He never submitted it, and Allan wasn't sure it should be in
the OEIS, so I created it.  Today I extended it to 15 terms using the data
in Peter's 2014 pdf file.

Incidentally Peter thanked me for creating the entry and said in reply that
he will try to find his old program and compute more terms.

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 Sun, Apr 18, 2021 at 7:52 PM Allan Wechsler <acwacw at gmail.com> wrote:

> I think writing to him is a great idea; get him to author that sequence,
> which he only deserves, after all.
>
> On Sun, Apr 18, 2021 at 1:39 AM Neil Sloane <njasloane at gmail.com> wrote:
>
> > PS I see that the author of that poster updated it in 2014, extending it
> to
> > 15 vertices:
> >
> >
> >
> https://math.chapman.edu/~jipsen/tikzsvg/planar-distributive-lattices15.html
> >
> > I am going to write to him
> >
> >
> > 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 Sun, Apr 18, 2021 at 1:17 AM Neil Sloane <njasloane at gmail.com> wrote:
> >
> > > Allan, I confirm your numbers.  I'll run it through Superseeker, which
> > > will tell us if it is a simple cousin of an existing entry, and if it
> > > doesn;t find anything I will add it - it will be A343161.
> > >
> > > Thanks for catching this fish!
> > >
> > > 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, Apr 17, 2021 at 9:22 PM Allan Wechsler <acwacw at gmail.com>
> wrote:
> > >
> > >> I forget how I stumbled on this:
> > >>
> > >>
> >
> https://math.chapman.edu/~jipsen/mathposters/Planar%20distributive%20lattices%20up%20to%20size%2011.pdf
> > >> .
> > >>
> > >> It is a chart purporting to show all of the planar distributive
> lattices
> > >> with up to 11 vertices. Like any true-hearted sequence fanatic I
> counted
> > >> the number of these guys of each order, and got the following
> sequence:
> > >>
> > >> 1,1,1,2,3,5,8,14,24,42,72...
> > >>
> > >> Imagine my surprise at finding this sequence missing from OEIS! The
> > author
> > >> is apparently Dr. Peter Jipsen, at Chapman University in California.
> > >>
> > >> Perhaps someone here can figure out (a) what a planar distributive
> > lattice
> > >> is, (b) whether Dr. Jipsen enumerated them correctly, (c) whether I
> > >> counted
> > >> them off Jipsen's poster correctly, and (d) whether to add the
> sequence.
> > >>
> > >> Thank you!
> > >>
> > >> --
> > >> Seqfan Mailing list - http://list.seqfan.eu/
> > >>
> > >
> >
> > --
> > Seqfan Mailing list - http://list.seqfan.eu/
> >
>
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