# [r-t] General case of an extent

Graham John graham at changeringing.co.uk
Mon Oct 27 00:37:51 UTC 2014

```Joe Norton asks:

> I was wondering if such a thing has ever been
> devised as a composition of an extent which
> can be extended to arbitrarily many bells.
>Either of a particular method or of methods
> with certain lead end groups and clean proof.

Plain Bob is straightforward as follows:

Extent of Plain Bob (all stages)

Minimus: no calls
Doubles: 3(a)
Minor: 3(3(a)b)
Triples: 3(3(4(a)b)c)
Major: 3(3(4(5(a)b)c)d)
Caters: 3(3(4(5(6(a)b)c)d)e)
Royal: 3(3(4(5(6(7(a)b)c)d)e)f)
etc

Where all calls a,b,c,d,e,f etc are Homes called from the 2nd (making 2nds).

No call (Minimus)
a = pn23 (Doubles)
b = pn234 (Minor)
c = pn2345 (Triples)
d = pn23456 (Major)
e = pn234567 (Caters)
f = pn2345678 (Royal)
etc

For example

720 Plain Bob Minor
123456
--------
135264
156342
164523
142635
a 124635
143256
135462
156324
162543
a 126543
164235
143652
135426
152364
a 125364
156243
164532
143625
132456
b 123564
--------
3 part.

a=pn1236, b=pn1234

These also give double extent round blocks for 2nds place Treble Dodging
methods e.g. 80640 Cambridge S Major.

Graham

```