# [r-t] New method - Auryn Differential Minor

edward martin edward.w.martin at gmail.com
Tue Dec 4 09:05:37 UTC 2012

```On 3 December 2012 20:07, Alexander Holroyd <holroyd at math.ubc.ca> wrote:

>.  The problem with -25- is that the parity of the
> rows for the section are +-+-, so the two rows with the treble in 3rds are
> the same parity.  The proof I know that the standard calling works requires
> paity structure +--+ or ++-- in each section.

This is the case if the method is symmetric but need not be so if asymmetric
eg
the first half lead gives the rows
231645 +
326154 -
321654 +
236145 -
had the method been symmetric, the second half would give
456123 -
541632 +
546132 -
451623 +
which would be hard to deal with, however, the asymmetric second half
gives the rows
426153 +
241635 -
246135 +
421653 -
and that aspect no longer exists.

Having the same half-lead rows and the same full-lead rows, whether 34
x 34 versus x 34 x in the sections when treble is in 5-6 or in 12
actually gives the same rows but in different sequence, so the
asymmetric method looks promising from that point of view

Eddie

```