[r-t] Composition search?

Philip Earis pje24 at cantab.net
Tue Nov 24 02:16:13 UTC 2015


"Yes, if I do have a go I'd be using a high level language and 
multithreading, potentially up to hundreds of threads"

Alan, if you're looking for juicy problem to get stuck into then personally 
I'd ignore trying to shave microseconds of a well-trodden Cambridge Major 
search, and instead have a look at one of the great unsolved compositional 
problems: an extent of bobs only Erin Triples.

This is very simple to describe. Erin is a simple method on 7 bells. It is 
comprised of 6-change divisions  A "plain" division ("p") has notation 
7.3.1.3.1.3, that is:

1234567
2143657
1246375
1423657
4126375
4213657
2416375

A "bobbed" division ("b") has notation 5.3.1.3.1.3, that is:

1234567
2143576
1245367
1423576
4125367
4213576
2415367

The challenge is to produce a composition for an extent (all 7! = 5040 
possible rows) consisting of just plain and bobbed divisions, as above.  (Or 
alternatively prove that no such possible peal composition exists, which 
would be disappointing and perhaps unexpected, but still a big theory 
milestone).

Fame (relative), if not fortune, will be showered on anyone who can solve 
this problem.  Best of luck!






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