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Cryptic crossword, Issue 20

Cryptic #8, set by Seuss: Download as a PDF or read on!

Across clues

  • 3. Debate the messy garment around uniform. (8)
  • 7. Drunk sort, you donut! (5)
  • 8. Flip heart to get third element. (2)
  • 9. Southern couple goes about introducing quirky rule to code square roots. (5)
  • 11. Slack organisation leads the (definitely humorous) university magazine. (9)
  • 13. Heartless warning of the problem that doesn’t ‘add up’. (6)
  • 15. Absurd ending to root expression. (4)
  • 18. Not down, not under, onto! (4)
  • 21. Kitten half-ate last shape. (4)
  • 22. while cryptic != solved:
         go round in circles. (4)
  • 23. Trolley intercepted by Descartes. (4)
  • 24. Example: initially, grab some items in one basket. (4)
  • 25. Lure into tangled net with frost. (6)
  • 27. Sangwin’s shapes, strangely, can reverse derivatives. (9)
  • 29. Itchy reeler cancels odds at half six. (5)
  • 32. $\mu=\rho V (v-at)$. (2)
  • 33. Cat beheaded after hospital spiral. (5)
  • 34. Base secret plan for my data table. (4,4)
  • Down clues

    • 1. A/hh! A hyperbola! (4)
    • 2. Del backed into 3/4 of curb. Del is crossed! (6)
    • 3. Record in fixing lumbar contraction. (5)
    • 4. Christmas lectures… during Christmas? (2)
    • 5. Milliequivalent of mass, energy and charge. (3)
    • 6. Hot or not: a reversal gate. (3)
    • 10. Engineer I rang is a ladder operator. (7)
    • 12. No issues, went inside, thank you! (6)
    • 14. “Eek!” (Goes outside around nerds). (5)
    • 15. Butcher loves to work out. (5)
    • 16. Rest, o-or cuckoo farm alarm? (7)
    • 17. Atomic centres alter nil cue. (6)
    • 19. Personal assistant measuring pressure. (2)
    • 20. Logic operation giving work-core. (2)
    • 24. Ned follows bear, gets decapitated, deserved. (6)
    • 26. Malty beer put out next to street. (5)
    • 28. Place to hide in Guatemala, ironic! (4)
    • 30. Hot or not: a Chappell Roan song starting. (3)
    • 31. A tree to reclimb regularly. (3)
    • 32. Odd muon shortens the moment. (2)
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    Dear Dirichlet, Issue 20

    Moonlighting agony uncle Professor Dirichlet answers your personal problems. Want the prof’s help? Send your problems to deardirichlet@chalkdustmagazine.com.

    Dear Dirichlet,

    I’m the groundskeeper at Edgbaston cricket ground, and England are playing a test match next month. The captain has not-so-subtly suggested to me that before England go out to bat, I should cut the grass extremely short under the rope around the outside. Is this friendly gardening advice, or does he have something up his sleeve?

    — Where’s Wolf, Derby

    Continue reading

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    Prize crossnumber, Issue 20

    Our original prize crossnumber is featured on pages 70 and 71 of Issue 19.

    Rules

    • In the completed crossnumber:
    • The number of entries that are even numbers is an even number;
    • The number of entries that are odd numbers is an odd number;
    • The number of entries that are prime numbers is a prime number;
    • The number of entries that are square numbers is a square number;
    • The number of entries that are multiples of 3 is a multiple of 3.
  • There is only one solution to the completed crossnumber. Solvers may wish to use the OEIS, Python, their ZX Spectrum, etc to (for example) obtain a list of prime numbers, but no programming should be necessary to solve the puzzle. As usual, no entries begin with 0.
  • One randomly selected correct answer will win a £100 Maths Gear goody bag, including non-transitive dice, a Festival of the Spoken Nerd DVD, and much, much more. Three randomly selected runners up will win a Chalkdust T-shirt. Maths Gear is a website that sells nerdy things worldwide, with free UK shipping.
  • To enter, submit the sum of all the digits in the row marked by arrows using this form by 14 April 2025. Only one entry per person will be accepted. Winners will be notified by email and announced on our blog by 1 June 2025.
  • Continue reading

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    What’s hot and what’s not, Issue 20

    Maths is a fickle world. Stay à la mode with our guide to the latest trends.

    HOT This shape

    Behold! A square. Not sure why we’ve decided that the ‘straight’ part of ‘straight lines’ isn’t important anymore but OK boomer.

    NOT Projectile motion problems

    This winter, we’re exclusively covering our bathrooms with keyhole shapes. Who’d live in a house like this…?

    HOT Being outraged at the Nobel prize

    Secretly you are all apoplectic your ChatGPT blog post wasn’t nominated.

    NOT Writing papers which qualify

    Getting your code to compile. That’s it. That’s the real Nobel prize.

    HOT Going on More or Less to talk about maths

    Maths people agreeing agreeably with maths people. In terms of peak radio, it’s not exactly Johnnie Walker’s Sounds of the Seventies… but what is?

    NOT Going on GB News to talk about maths

    But I guess the money’s good, right? Right?

    HOT Overnight temperatures on 10 October

    No need to worry about putting the heating on tonight. Thanks, BBC Weather!

    NOT Sanity-checking your supplier’s data before publishing it everywhere

    The Met Office would never have given such dodgy data.

    HOT -T-O-G-O

    Mathematicians like a well-defined dance

    HOT Taking long exposures of the sky and telling your friends you saw the northern lights

    Nothing to do with maths, it’s just literally all our group chats right now.

    NOT The Northern Lights trilogy

    Did Mick Herron write it? No? Then I’m not reading it.

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    The big argument: should we write another issue?

    Yes, argues Sam Kay

    The reason we spend months writing this magazine is because the fans love it. It’s cool, it’s hip, it’s Cosmo. Don’t believe me? Here’s a proof by induction.

    It’s trivial that the first ever issue of Chalkdust was fun to read. If not for its great initial success, I wouldn’t be here writing!

    Our ever-expanding mailbox and letters pages tells us it is safe to assume that $n$ issues of Chalkdust are fun to read.

    Now, take a group of $n+1$ issues of Chalkdust and consider only the first $n$ issues. From the above assumption, these $n$ issues are fun to read. Likewise, consider the last $n$ issues of Chalkdust. These issues also have to be fun to read by the same assumption!

    Since both the first $n$ issues and the last $n$ issues overlap by at least one issue, this overlapping issue will be as fun to read as the rest, and thus all $n+1$ issues of Chalkdust are fun to read.

    If $n$ issues of Chalkdust are fun to read, then we have proven that $n+1$ issues of Chalkdust are also fun to read. And we already noted that the first issue was indeed fun to read. By induction, any issue of Chalkdust we release will be fun to read. So we probably should release another.

    No, argue the rest of the team

    Have you seen the magazine?!

    Sure, we have a lovely selection of articles by lovely authors, and you lot are a lovely audience… but have you seen the pages between the articles? It’s all low effort trash, placeholder text we forgot to update, inconsistent use of Oxford commas, and repeating the word ‘lovely’ multiple times in the same sentence.

    Surely by now, a decent publication would have accidentally come up with at least one good joke.

    Half the reviews are of one-off events that you’ve missed.

    The letters that Dirichlet receives aren’t even real.

    We’ve been on Have I Got News For You—the ultimate aim of any niche publication—but where else is there to
    go? In the bin.

    We realised early on that they’ll let you print anything, but should they really be printing this?!

    Then again, printing this is quite fun, and we already have one passable pun for Dear Dirichlet 21. Better write the rest of the magazine then.