[r-t] 147 TDMM

[Graham John]

RAS wrote:

> However we can now definitively say that you need at
> least twelve extents to get all 41. 

Some care, or at least caveats, is needed with statements like this. There
are three constraints that are being applied, if removed, can reduce it
further:-

1.  No singles
2.  No half-lead spliced
3.  No MEBs

For example, there are groups of half-leads of London and Cambridge that
contain the same rows when rung out of course to each other. They can't be
pieced together on their own, but could be patched into extents with other
methods. The next stage of the research perhaps?

Graham