[r-t] internal runs

[Mark Davies]

Ander writes,

> There are 1002 such rows (if my use of the inclusion-exculsion principle
> is correct).  Can it be done in a way that anyone would want to ring?

I remember composing a qp of Duffield for an attempt some time in the 
90s. I had noticed that the construction of Duffield rendered the 
production of runs across the middle places 3-6 quite easy, so I packed 
lots of them into the final composition. We rang it. Less than 
inspiring, sadly.

MBD