[r-t] Complexity of extents

[Alexander Holroyd]

I vaguely remember that PABS had an extent of the principle 
7.1.7.1.7.1.345 with calls 3 and 5 that exploited an unusual kind of 
symmetry.  (Perhaps he would care to remind us).
A

On Mon, 24 Jun 2013, Richard Smith wrote:

> Andrew Johnson wrote:
>
>>> From: Richard Smith <richard at ex-parrot.com>
>>> But when I try to get an extent with rotational symmetry, it
>>> feels like I'm fighting against the symmetry rather than
>>> utilising it.
>>> 
>> It's not an extent, but for rotational symmetry were
>> you thinking of compositions such as Ander's 5024 Bristol S.
>> Major?
>
> Not really.  I think the difference between an extent an eighth-extent (a 
> peal of major) is significant.  I was thinking more of extents on four, five 
> or six.  I can't say I've ever tried to produce a rotationally symmetric 
> peal of major.
>
> Naïvely you wouldn't necessarily expect a rotationally symmetric extent to 
> be any harder to produce than a palindromic one.  Both symmetries constrain 
> half of the rows.  But, at least in my experience, a rotationally symmetric 
> extent (that's not also palindromic) feels a much tougher proposition than a 
> palindromic one.
>
> RAS
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