[seqfan] Re: A000105 Free Polyominoes

[John Mason]

Tom
Thanks, the G4G link looks good enough to be able to enrich the Wikipedia page.
john

Sent from Mail for Windows 10

From: Tom Duff
Sent: 09 March 2021 19:12
To: Sequence Fanatics Discussion list
Subject: [seqfan] Re: A000105 Free Polyominoes

Doesn't look like it's in that paper, which I found here:
https://dspace.jaist.ac.jp/dspace/bitstream/10119/13757/1/21457.pdf
Possibly this: https://www.gathering4gardner.org/g4g10gift/math/Shirakawa_Toshihiro-Harmonic_Magic_Square.pdf
I think there's a more legit reference describing how Shirakawa counts
them, but it's not mentioned in his G4G paper and I can't find it
right now.
The obvious way to get free polyomino counts is to count fixed
polyominoes with various symmetries and use the Frobenius-Burnside
counting formula.

On Tue, Mar 9, 2021 at 9:25 AM John Mason <masonmilan33 at gmail.com> wrote:
>
> Hi seqfans,
> A000105 lists the numbers of free polyominoes through a(45).
> Wikipedia on the other hand states that values are known through a(28).
> I assume the new data comes from  “D. Xu, T. Horiyama, T. Shirakawa, R. Uehara, Common Developments of Three Incongruent Boxes of Area 30, in Proc. 12th Annual Conference, TAMC 2015, Singapore, May 18-20, 2015, LNCS Vol. 9076, pp. 236-247.”
> Would anyone with access to the article like to update Wikipedia?
> john
>
>
>
> --
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
>
> --
> Seqfan Mailing list - http://list.seqfan.eu/

--
Seqfan Mailing list - http://list.seqfan.eu/



-- 
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus