[seqfan] Re: Unique Products Regarding Binary Matrices
Leroy Quet
q1qq2qqq3qqqq at yahoo.com
Fri Jun 11 22:32:23 CEST 2010
Richard Heathfield on sci.math/rec.puzzles has found two other solutions (that are not rotations, reflections, or color reversals of each other or of Rob Pratt's solution).
http://groups.google.com.sg/group/sci.math/browse_thread/thread/4b5bda92e3b9a34a/1b76db6d1e455bcf#1b76db6d1e455bcf
Thanks,
Leroy Quet
[ ( [ ([( [ ( ([[o0Oo0Ooo0Oo(0)oO0ooO0oO0o]]) ) ] )]) ] ) ]
--- On Fri, 6/11/10, Rob Pratt <Rob.Pratt at sas.com> wrote:
> From: Rob Pratt <Rob.Pratt at sas.com>
> Subject: [seqfan] Re: Unique Products Regarding Binary Matrices
> To: "Sequence Fanatics Discussion list" <seqfan at list.seqfan.eu>
> Date: Friday, June 11, 2010, 6:34 PM
> 18:
>
> 0 0 0 0
> 0 1 1 1
> 1
> 0 0 1 0
> 0 0 0 0
> 1
> 0 0 0 0
> 0 0 0 1
> 1
> 0 1 0 1
> 0 1 1 1
> 0
> 0 1 0 1
> 0 1 0 1
> 0
> 1 1 0 1
> 0 1 1 1
> 0
> 0 0 0 1
> 1 1 0 1
> 0
> 0 0 0 0
> 1 0 1 0
> 1
> 0 0 0 0
> 1 0 0 1
> 0
>
> Note that for n = 9, there are exactly 18 possible products
> (the ones you list below, and 1), so each one must be used.
>
> Rob
>
> -----Original Message-----
> From: seqfan-bounces at list.seqfan.eu
> [mailto:seqfan-bounces at list.seqfan.eu]
> On Behalf Of Douglas McNeil
> Sent: Friday, June 11, 2010 11:57 AM
> To: Sequence Fanatics Discussion list
> Subject: [seqfan] Re: Unique Products Regarding Binary
> Matrices
>
> > I too have been able to get 16 unique products. But
> getting those last 2 products to differ is a *little*
> tricky, perhaps, if possible.
>
> I can get 17 -- set([2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14,
> 15, 16, 18,
> 20, 24, 27]) -- but not 18 yet.
>
>
> Doug
>
> --
> Department of Earth Sciences
> University of Hong Kong
>
>
> _______________________________________________
>
> Seqfan Mailing list - http://list.seqfan.eu/
>
>
>
> _______________________________________________
>
> Seqfan Mailing list - http://list.seqfan.eu/
>
More information about the SeqFan
mailing list