The Aperiodical

This number of the All Squared podcast contains the final third of our interview with the inestimable David Singmaster, and then a bit from CP about his favourite book, “A treatise on practical arithmetic, with book-keeping by single entry“, by William Tinwell. The first part of the interview, and plenty of links to go with it, were in Number 5 of the podcast. Here are some links to the things we referred to in this podcast: The Casa di Galileo. The Internet Archive has scanned in Dickson’s History of the Theory of Numbers (and Volume 2 and Volume 3). David’s notes are written in the SCRIPT markup language. If you know anything about it and have an idea of how to put it on the web, please get in touch. The Internet Archive also has a scanned-in copy of the fifth edition of Christian’s favourite book, A Treatise of Practical Arithmetic (the “of” seems to have changed to “on” for the sixth edition). Tynemouth Market. The MathsJam annual conference is attended by not just David, Katie and CP, but a whole load of people who are really passionate about recreational maths in all its forms. Registration for the 2013 meeting has just opened – you know what to do! Finally, here are some pictures of Christian’s favourite book, so you don’t just have to imagine what he was talking about: We hope you enjoy listening to this two-parter. We certainly enjoyed recording it!

Good maths books are simultaneously plentiful and rare. While there are a few classics almost everyone knows about and has copies of (Gardner, Hardy, etc.), the trade in lesser-known maths books is considerably less well-organised. Very few bookshops have well-stocked maths sections, and insipid pop maths books dominate. Unless you hear about a good maths book through word of mouth, you’ll often only encounter it once it’s ended up in a second-hand bookshop, usually a refugee from an emptied maths department library. But books, more than anything else, are where the beauty of maths really manifests itself. It’s where ideas are presented most clearly, after they’ve had time to percolate through a few more brains. We talked to David Singmaster, professor of maths and metagrobologist, about his favourite maths books. Here are some links to the things we referred to in the podcast, along with some bonus extras: The Slocum Puzzle Collection at Indiana University Luca Pacioli on Wikipedia Scans of the manuscript of De Viribus Quantitatis The Conjuring Arts Research Center’s edition of De Viribus Quantitatis The one pile game (Static Nim) Nim on Wikipedia Nimber on Wikipedia Nim Multiplication by Lenstra (link goes to a big PDF) The game that wasn’t solved was Sprouts, which is analysed using nimbers in Computer analysis of Sprouts with nimbers by Lemoine and Viennot Winning Ways for your Mathematical Plays by Berlekamp, Conway and Guy Melancholia by Albrecht Dürer at the British Museum (it’s also the icon for our Arty Maths section over there on the right!) The Blind Abbess and her Nuns at The Puzzle Museum The vertical-horizontal illusion at Wikipedia George Hart’s page on De Divina Proportione (and one on Leonardo da Vinci’s illustrations) Scans of De Divina Proportione at archive.org The drawings CP was thinking of were from the Codex Guelf, and posted at BibliOdyssey. Between 1981 and 1985 David edited and published Cubic Circular. With David’s permission, Jaap Scherphuis has put every issue online. CP recommends Westwood Books in Sedbergh and Barter Books in Alnwick as sources of unusual second-hand maths books. The chap who runs Westwood is an ex-mathematician and does a good job of saving books being thrown out of university libraries. Part 2 will appear next week.

It’s a repeat booking for the Festival of the Spoken Nerd in number 4 (or 16 if you belong to Team All Squared) of our podcast. Standup mathematician Matt Parker joined us to talk about interesting coincidences. Here are some links to the things we referred to in the podcast, along with some bonus extras: The operator precedence problem that makes Katie want to cry Colin Wright has blogged about it Chocolate maths! Robert Munafo’s Notable properties of specific numbers The Online Encyclopedia of Integer Sequences A135650 – Even perfect numbers written in base 2 A002904 – Delete all letters except c,d,i,l,m,v,x from n then read as Roman numeral if possible, otherwise 0 A000012 – The simplest sequence of positive numbers: the all 1’s sequence. The episode of Relatively Prime about interesting number facts, including the OEIS. Matt Parker plugged a couple of things: Festival of the Spoken Nerd Maths Gear Matt’s solo show, The Number Ninja Next time, which should be soon, we’ll be talking to a Fantastic Mystery Guest about our favourite maths books.

Remember, remember, The fourteenth of March. While the previous number of All Squared failed to achieve topicality by appearing several weeks after the event it was about, this time we’ve hit the nail bang on the head with a podcast all about π day… on π day! We chatted to Festival of the Spoken Nerd’s Steve Mould about remembering π – how much can you memorise; how much should you memorise; and if you really insist on memorising it, what’s the best way to do it? Here are some links to the things we referred to in the podcast, along with some bonus extras: The number of this episode is 3, which is exactly π if you don’t think very hard when you read the Bible A chronology of the computation of π Epic π quest sets 10 trillion digit record, at New Scientist Download 4 million digits of π “Using pi calculated out to only 39 decimal places would allow one to compute the circumference of the entire universe to the accuracy of less than the diameter of a hydrogen atom.“ The π Code – π in base 26 ≈ D.DRSQLOL 33,333 digits of π in base-(the 1000 most common words in the English language) Japanese breaks pi memory record on BBC News (in which “Conventionally, 3.14159 is used as pi.”) Japanese man claims new record for memorising ‘pi’ at the Daily Mail (in which “It is usually written out to a maximum of three decimal places, as 3.141, in math textbooks.”) Akira Haraguchi The official world record for memorising π is held by Chao Lu of China, who memorised 67,890 decimal digits. Kolmogorov complexity (Steve had the definition right – it measures just the length of the description of the thing, and doesn’t measure the resources required to interpret that description) Normal number Find your birthday in π Find any string of digits in π Michael Hogg’s method of memorising 100 digits of π Joshua Foer: Moonwalking with Einstein – a talk about a book about memory Irrational sonnets (where the stanzas have 3,1,4,1,5 lines) in French, or in English A mnemonic for π which is also a pangram, in French Previously on The Aperiodical: Random walks on π, a marvellous visualisation of the digits of π. Circular reasoning: who first proved that $C/d$ is a constant? – a historical essay by David Richeson. While Steve was chatting to us, his collaborator Matt Parker was measuring π with pies for Numberphile. Steve Mould has his fingers in, if you’ll excuse one final pun, many pies. Here are some links to some of his projects you might find interesting: Steve’s homepage Festival of the Spoken Nerd Maths Gear Steve’s on Twitter

Here’s the second edition of our new podcast, All Squared. This time we talked to Dr Andrew Taylor, PhD, about nonsense formulas in the news. In particular, since we recorded very close to pancake day, we took a close look at the various “formulas for the perfect pancake” printed in UK newspapers. Here are some links to the things we referred to, along with some further reading. Since we found so many nonsense formula stories, I’ll split the links into two sections: nonsense and the rest. Nonsense formula stories Flipping clever! Formula for the perfect pancake revealed by maths boffins (but we’ll still end up with ours stuck to the ceiling) – Daily Mail (2013) The perfect pancake? Easy, just follow this formula … 100 – [10L – 7F + C(k – C) + T(m – T)]/(S – E) – Daily Mail (2009); the one with the amazing stock photo Formula for perfect pancake unveiled by scientists – The Telegraph (2009) How to toss the perfect pancake – Daily Express; the one without the actual formula The perfect pancake toss – Shortlist; includes the formula Why today’s the perfect day to change your life – Daily Mail Revealed: The formula for a perfect family Christmas – drink two parts wine for every three chocolates – Daily Mail Scientists are serious about having a laugh – The Telegraph Scientists reveal formula for the perfect sitcom – The Telegraph Horror’s perfect formula – London Evening Standard; the one where “blood and guts” = $\sin x$. Here’s my happy marriage secret: avoid romance – The Telegraph The formula for perfect parking  – NPR The rest The geometry of perfect parking – Simon Blackburn; PDF The Tommy Westphall universe Jewish Problems – Tanya Khovanova’s collection of Russian “coffin” problems on the arXiv, including number 1’s quickly-read puzzle. Mathematical Puzzles, a Connoisseur’s Collection, by Peter Winkler The Muddy Children: a logic for public announcement – slides by Jesse Hughes CP’s Interesting Esoterica collection Number 3 will appear in exactly 9 days. You can probably guess what it’ll be about. But can you guess who we’ll be talking to? You can subscribe to All Squared through our RSS feed. We’ll set up an iTunes thing if anyone asks for it.

We’ve been quietly making plans and gathering material for a new project over the past couple of weeks, after noticing that there’s an unusual paucity of maths podcasts at the moment. Well, that exciting new project is now happening, and it’s a half-hour podcast featuring maths, guests, puzzles and links from the internet. It’s called All Squared, and it’ll contain cringe-inducing intro/ending contrivances, interesting guest interviews on topical and other subjects, and a panoply of mathematical curiosities. This is the first number of the podcast (we thought ‘episode’ would set unrealistic expectations of regularity, and we can never resist a pun). It includes an interview with Edmund Harriss about spoken mathematics, as well as a puzzle which we’ll give the answer to in the next number, and a great mathematical flash game to keep you occupied until that appears. Here are some links to the things we referred to, along with some further reading: Mathematics Out Loud at Maxwell’s Demon, Edmund’s blog Milton’s Paradise Lost (Project Gutenberg ebook version) The Pythagorean Proposition, a book containing nearly 370 proofs The proof of Pythagoras’ theorem that Katie gave Pythagorean Theorem poem Maths Poetry at Mr P’s Maths Page Gunfight at the cubic corral – Thony Christie on Cardano, Tartaglia and 16th Century maths competitions The same topic at The Story of Mathematics CP’s proof without words on YouTube Edmund says Sphere Packings, Lattices and Groups by John Conway is particularly readable. Z-Rox, the dimensionally deficient game, at Kongregate Number 2 (or should it be 4?) will appear soonish.

Two days late, because that is the way we rotate here, it’s another episode of our sporadic navel-gazing podcast. In this episode we talked about: Our piece on the Invariant Subspace Problem (and the more recent news) Log-log! Who’s there? Not a power law! Our coverage of the new Mersenne Prime news, and our meta-coverage of everyone else’s coverage of it The good, the bad, and Gowers Interesting comments discussion on the ‘What is a mathematician’ post The first in Katie’s series of Open Season posts, on Singmaster’s Conjecture Please consider hosting the Carnival of Mathematics Mysterious upcoming project – watch this space As always, we’re keen to hear about your mathematical exploits either by email to root@aperiodical.com or through our new, streamlined sending-something-in form.

After two months we’ve finally done another podcast! We completely forgot even the most rudimentary things about how to do a podcast. Sorry. In this episode, we talked about: Mathematical Christmas cracker jokes Fractal Christmas trees Posts from MathsJam speakers – Tom Button on Radii of Polyhedra and Phil Harvey on AS Results and Batting Averages The Aperiodical’s Mathematical Survey Carnival of Mathematics 94 As always, we’re keen to hear about your mathematical exploits either by email to root@aperiodical.com or through our new, streamlined sending-something-in form. If you’ve got some ideas for how we can do a better podcast, we’d be particularly keen to hear from you.

We took the opportunity of us all being in the same small slice of space and time (MathsJam, last weekend) to record another episode of our continuing audio part-work, The Aperiodcast. We talked about: Christian’s Recreational Maths Seminar Dara O Briain: School of Hard Sums to return; maths students sought to take part Matt Parker’s Twitter Puzzle – 12th Nov John McKenna’s helpful comment about our title font As always, we’re keen to hear about your mathematical exploits either by email at root@aperiodical.com, our twitter @aperiodical, or whatever means you can think of to get in contact with us.

Here’s another episode of our irregular podcast about what’s been happening on the site. This time, we talked about: Advances in pure nonsense Robert Schneider, Mathematical Musician/Musical Mathematician #MTT2K: Teachers critique Khan Academy Surds: what are they good for? Calculus of the Nervous System The new fonts on the site Christian’s new Aperiodical Round Up and Interesting Esoterica Summation Puzzlebomb October 2012 Christian apologises for the poor sound quality, an unavoidable consequence of being at the family home for the weekend without a proper microphone. As always, we’re keen to hear about your mathematical exploits either by email at root@aperiodical.com, our twitter @aperiodical, or whatever means you can think of to get in contact with us.