Oh dear, one of those dreaded numericals again! I print the grid and clues and retreat out of firing range. Well, not exactly out of range. This doesn’t look quite as daunting as the numerical ones sometimes are. We have to simply use Square, Prime and Neither the one nor the other. That is almost within my range of mathematical understanding. SPORN is an intriguing title and, as I check clues to confirm that Hedgehog doesn’t even begin to qualify for the Listener Setters’ Tipply club, I wonder whether he is indulging in Special PORN instead but the other Numpty points out that that amusing title is simply Square, Prime OR Neither the one nor the other. Over to the other Numpty.
This puzzle was one that was very approachable, not needing any progamming or access to Mathematica. Even the clues were simple to interpret, for once, just S, P and N instead of A to Z or worse. And decimal notation, too. A table of primes in the range 2-9973 (at http://www.mathsisfun.com) (for 5d) and squares in the range 1-99999 (4d) would do, and these were easy to find on the internet.
Where to start? Perhaps 6d, where form SS, 1x, 4x or 9x, offers only 16 and 49 as possibles. 9a will help now, PSS, which is 2xx,3xx,5xx or 7xx. Only 25x and 36x are possible forms, and PSS forces this to be 256. So 6d is 16, and 9a is 256. Looks hopeful.
Now 9d is PSNS, so 25xx, and in fact only 2500 fits. 11a is NNS ending in 5, so only 225 or 625, forcing 625!
Try something harder? 4d is SPNNS, so 1x2xx, 4x2xx or 9x2xx. As 4a is SSNN, 9xxxx is not on, and 20a is SNPS, forcing the last digit of 4d to be 1, 4 or 9. The tables oblige this 4d to be 43264. Building out from there filled almost half the grid.
I got into a muddle in the bottom left, so tried a second front from 7a, PPP. This gave a list of 14 possibles from 233 to 797. As 8d is PS, those ending in 1, and 9 could be discarded So could the ending 7, as there are no squares 7x. Happy result, as all 6 remaining options for 7a ended in 3, making 8d 36, but a temporary dead end. 1a on table inspection for PNPS only offered 5476. Soon grid was full with some apparent choices to be made at 10a, 3d and 11a. Unique entries forced 10a to be 46, not 96. I admit that I then gazed foolishly for a while at 3d and 11a (NNS), which seemed illegitimately ambiguous, until I remembered at last that 2 is a prime so 3d had to end in 6.
I enjoyed this, and it was a great “have a go” one to encourage those who might think that the numerics aren’t their thing at all. Could the preamble have stated that “no special tools are needed” to entice some fainthearts, a little like the Magpie A to E ratings? Anyway, well done, Hedgehog.
It was difficult to illustrate this week’s with bales of tea being flung into the ocean or a lovely lady with yellow cheeks and black teeth, but how about a coloured grid - red on yellow for primes, pink for squares, blue for neithers, and aqua backgrounds for definitely odd numbers where P occurred anywhere after the first letter of a clue?