Oh my goodness this one took some solving! First, congratulations Zag on your great choice of title – another contender for best title of the year.

Prime Cuts set a record for me – 17 pages of meticulous working and an elapsed time of a week. I came to the Listener via the numericals and I enjoy solving them, but had I not been so keen, I may have been tempted to give up.

In fairness one page (but only one) of the 17 was reworking caused by a certain mathematician telling me that there were 3 pairs of reversible primes, rather than the actual 4. That sorted, it was a steady and rather strenuous uphill climb to reach the gridfill. I confess I was hoping for some sort of a revelation in the 21 letters but with all the vowels absent that was unlikely (I hope I haven’t missed it).

Without the test for triangular numbers (8n+1 gives a square number), kindly supplied by said mathematician in penance for his earlier misinformation, Prime Cuts would have taken me even longer. Still, I’m proud of finishing it and I’m glad I didn’t need to resort to the offer of Mathematika.

Thanks Zag for providing a week on and off of sustained mental workout,

Gill