Wrong, But Useful: Episode 53


In this month’s episode of Wrong But Useful (#53), brought to you by the power of Lemsip and a day in bed, Colin and Dave are joined by Special Guest Co-Hosts @sean_jamshidi and #NikiWithoutTwitter, who are Sean Jamshidi and Niki Kalaydzhieva from Chalkdust Magazine1 in real life.

  • Niki is an analytical number theorist with an interest in outreach; Sean studies oceanic fluid dynamics.
  • We beat our own world record for the most shambolic number of the podcast. It’s 5,830, the sum of the first 53 primes and $53 \times 110$; this will be the last such number until episode 853.
  • Colin and Niki have both read @vickymaths1729’s Closing The Gap and loved it. We talk about the Polymath projects.
  • Niki claims Chalkdust2 is the best maths magazine ever, which is off-script. Sean and Niki are (at the time of recording) putting Issue 7 together, due out 2018 March 13.
  • The ICM is happening in Brazil this year; we have several suggestions for improving the Fields Medal. Niki mentions Chalkdust Magazine3 and their interviews with various laureates.
  • Niki and Sean did fantastic work in October on Black Mathematicians Month. We mention an article by Jonathan Farley. Sean mentions @minoritySTEM; also, @alomshaha is interested to hear from anyone interested in Black History Month.
  • Dave brings up superpermutations. Niki brings a theorem! Colin messes up simple arithmetic. Lovely example of something that starts off in a nice sequence, then breaks; it continues in a different nice sequence, then breaks that. Credit to a Numberphile video.
  • We had e Day on 2/7/18 (US style) and how we write dates and addresses backwards. XKCD and the ISO agree with Colin. Chalkdust4 comes out on $\pi$ Eve.
  • A post by @mathsjem about Victorian vocabulary.
  • Were Venn diagrams banned under the junta in Argentina?
  • Last month’s puzzle: A gold star for @chrishazell72 for finding the three holes in @stecks’s bit of paper.
  • This month’s puzzle, via @panlepan: What is the smallest positive integer that doubles when its final digit is moved to the front? (For example, 1729 becomes 9172 when its final digit is moved to the front, but 9172 isn’t double 1729.)
  • Niki and Sean remind everyone that Issue 7 of Chalkdust5 is due out the day before Pi Day, 2018-03-13.
  • We manage to make a shambles of the completely spontaneous ending, too!


Colin is a Weymouth maths tutor, author of several Maths For Dummies books and A-level maths guides. He started Flying Colours Maths in 2008. He lives with an espresso pot and nothing to prove.

  1. It’s a magazine for the mathematically curious, apparently. []
  2. A magazine for the mathematically curious []
  3. A magazine for the mathematically curious []
  4. A magazine for the mathematically curious []
  5. A magazine for the mathematically curious []


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