[r-t] Bobs only Grandsire

Philip Saddleton pabs at cantab.net
Mon Jun 12 17:25:05 UTC 2006


With an even number of bobs in a Q-set, there is no obvious reason why 
bobs-only extents of Grandsire shouldn't exist at even stages. For 
Minor, an exhaustive search rules it out in a matter of seconds, but is 
there a simple proof that it is impossible? It seems that with each 
Q-set forcing four B-blocks to be rung in a particular direction there 
is not enough room for manoeuvre.

Including them in both directions is not a problem:

1440 Grandsire Minor
23456   1  2  3  5
------------------
64235   -     -  -
42365   -  - [-] -
54326      -     -
------------------
8-part, omit [-] in alternate parts
Contains each row at back and hand.

How about an extent of Major?

-- 
Regards
Philip
http://www.saddleton.freeuk.com/






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