I suspect I’m far from unique in having thought about QR codes as a possibly useful tool for a thematic crossword. That said, trying to make a crossword that doubled as a QR code initially seemed like a lost cause. After all, the smallest possible normal QR code is 21×21 pixels – too large!

I only came across the Mandelbrot Set a few years ago on the Youtube channel Numberphile, which I find very interesting.

I have been delighted to see the recent increase in the number of blogs on the Magpie site, following my rallying cry earlier in the year. It would be churlish of me not to contribute to their number again – and reiterate my eagerness to read many more – so here are some thoughts on Splitting the Atom, aka my first failure as a setter.

I was sorry that much of the reaction to Irrational concerned the ambiguity surrounding the C and F values. In retrospect this could have been avoided by clarifying in the preamble that √C was a surd and that F had to be a positive integer.

A few solvers have asked for a brief blog on how I managed to construct two such Playfairs. Having read the editorial comment in Issue 259 that “Anyone who was astounded that Arcadia came up with Playfair-encoded real words might be disappointed to discover that this is something that is… reasonably feasible for a human-computer team”, I wondered whether it was worth saying anything! However, here are a couple of snippets readers might find useful.

The idea for Squares in Magpie 257 came from a little problem I created for my pupils some time ago:

Having enjoyed the recent flurry of setters’ blogs, perhaps it’s worth writing a few words about setting Sketchy, which was my first attempt at setting a thematic cryptic.

With Sondheim being a noted fan of themed cryptic crosswords (while I’m a big Sondheim fan in return), I was aiming to prepare something as a form of tribute in time for his 80th birthday in March 2010. I saw a production of Sunday in the Park with George in 2009, and explored that for possible themes – and a little in haste, compiled a puzzle that year based on a form of George Cross intertwining the names Sondheim and Seurat, with some pointillism-style markings to fill other cells. But it wasn’t satisfactory – the dots in the grid didn’t have any particular purpose or present a recognisable image, nor indeed were they coloured in any way, and there was no real endgame. A test solver told me as much, so I put it to one side in the hope of making radical amendments in time for Sondheim’s 90th in 2020 (some hope!)

How did Navigation get created, and who is Stymphalides? This blog answers these questions, in the same order!

I can’t remember where I first encountered the complaint tablet to Ea-Nasir. It’s a remarkable combination of commercial and personal gripes — in which the author, Nanni, lashes out not just at the poor quality product he’s been fobbed off with, but also the slight he feels from being disrespected. You can imagine reading this text as an online review some time in the early 2020s; except Amazon don’t sell copper ingots, and this was written in 1750BC.