[seqfan] Re: Subsets with prime sums again - Part 2

zak seidov zakseidov at yahoo.com
Wed Oct 28 15:14:50 CET 2009



--- On Wed, 10/28/09, Christopher Gribble <chris.eveswell at virgin.net> wrote:

> From: Christopher Gribble <chris.eveswell at virgin.net>
> Subject: [seqfan]  Subsets with prime sums again - Part 2
> To: "'Sequence Fanatics Discussion list'" <seqfan at list.seqfan.eu>
> Date: Wednesday, October 28, 2009, 9:33 AM
> Here is another triangle whose column
> sums give Zak's sequence
> 
> 4, 26, 444, 11998, 382716, 15844060, .
> 
>  
> 
> This is related to the method of subset construction.
> 
> For N = 2, the subsets are {1, 2}, {1, 4}, {2, 3}, {3, 4}.
> 
> The first member is 1 in 2 subsets, 2 in 1 subset and 3 in
> 1 subset.
> 

>             Frequency with
> which first
> 
>             subset member
> values occur
> 
> First   N   2   
>   3      4
> 
> Member
> 
>  1          2     
> 8    111
> 
>  2          1     
> 8     88
> 
>  3          1     
> 4     67
> 
>  4             
>    4     55
> 
>  5             
>    1     42
> 
>  6             
>    1     32
> 
>  7               
>        23
> 
>  8               
>        15
> 
>  9               
>         6
> 
> 10               
>         3
> 
> 11               
>         2
 
> Total       4 
>    26    444
 
> 
> This triangle is not in the OEIS either.
> 
Christopher, 
(as Neil just said)
go ahead! Submit it!
Best, 
Zak

 > Best regards,
> Chris Gribble
 



      




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