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A more equitable statement of the jealous husbands puzzle

Every time I use the jealous husbands river crossing problem, I prefix it with a waffly apology about its formulation. You’ll see what I mean; here’s a standard statement of the puzzle:

Three married couples want to cross a river in a boat that is capable of holding only two people at a time, with the constraint that no woman can be in the presence of another man unless her (jealous) husband is also present. How should they cross the river with the least amount of rowing?

I’m planning to use this again next week. It’s a nice puzzle, good for exercises in problem-solving, particularly for Pólya’s “introduce suitable notation”. I wondered if there could be a better way to formulate the puzzle – one that isn’t so poorly stated in terms of gender equality and sexuality.

Photomath can read my writing

I remember when OCR of mathematics was such a difficult problem that there was no good solution. I remember hints some years ago that the then-current version of InftyReader could do a reasonable job of taking a PDF document and converting it into LaTeX code, but it was far from perfect.

Today my phone told me that the app Photomath has an update and now supports handwriting recognition. This means I can write something like this:

and Photomath does this with it:

Exam timing

When I have been involved with running exams (I wasn’t, really, this year), special care seems to be made to spread these out so that where possible students don’t get exams bunched together. Still, I’ve heard students complain “we only have one day off between the Monday and Wednesday exams, that isn’t enough time to revise for the second topic”. I have a lot of sympathy for this; assessing a module (or proportion thereof) by how you perform in a one-, two- or three-hour window is quite a problematic arrangement, and if you haven’t had sufficient time to get up to speed on the topic, even more so. But I have had in mind that, essentially, “when I were a lad, we had it much worse”. Clearing out some boxes to move house, I found exam timetables from five of the six semesters I spent as an undergraduate, so now I can confirm or refute my feeling on this, in the latest of my series of posts that are surely only of interest to me.

Particularly mathematical Birthday Honours 2016

With the announcement the Queen’s Birthday Honours list, it’s time for the latest in our ongoing Honours-watch series of posts. In this, we search arbitrarily for ‘mathematics’ in the PDFs of the various lists, and hope our well-informed readers fill in the blanks where actual knowledge is required.

  • Prof. Alice Rogers, Emeritus Professor of Mathematics, King’s College, London, appointed OBE for services to Mathematics Education and Higher Education.
  • John Sidwell, volunteer, HMP Hewell appointed MBE for services to Prisoners through One to One Maths.
  • Danielle George, vice-dean for teaching and learning, Faculty of Engineering and Physical Sciences, University of Manchester, appointed MBE for services to engineering through public engagement.
  • Anthony Finkelstein, professor of software systems engineering, University College London and the Alan Turing Institute, for services to computer science and engineering.
  • Economist Angus Deaton, professor, Princeton University, Nobel laureate, for services to research in economics and international affairs.
  • Prof. Alan Thorpe, lately Director-General of the European Centre for Medium Range Weather Forecasts, appointed OBE for services to environmental science and research (thanks to Philip Browne on Twitter).
  • Prof. Nalini Joshi was made an Officer of the Order of Australia (AO); the citation is more involved than the UK ones and reads “for distinguished service to mathematical science and tertiary education as an academic, author and researcher, to professional societies, and as a role model and mentor of young mathematicians” (added in an update 16/06/16).

It’s also worth mentioning the new batch of Regius professorships, 12 posts created at universities around the UK to celebrate the Queen’s 90th birthday: Oxford University has been given a professorship in maths, but no appointment has been made yet.

Are there any others we’ve missed? Please add any of interest in the comments below. A full list may be obtained from the Cabinet Office website.

“How can you do coursework for maths?” What I marked this year

A while ago I was helping out at an open day. The material presented gave some information about the range of assessment types we use. A potential applicant asked me “how can you do coursework for maths?”. She felt that (what she understood as) maths could only be assessed by examination. (This is presumably because her experience of the English school system has not exposed her to anything but exams for maths.)

I thought it might be interesting (to me, at least) to list the types of assessment I’ve been involved in marking in the 2015/16 academic year.

Relatively Prime Season 3 Kickstarter

Relatively Prime - Kickstart Season 3

Samuel Hansen’s Relatively Prime has now published all episodes of the second season, available at, and the Kickstarter for Season 3 is now live. In fact, it’s so live it’s almost run its course: the third season will only be funded if at least $24,000 is pledged by Saturday 12th March 2016 at 4am GMT. At the time of writing, as I just pledged my support, the project is 30% backed.

Consider supporting this third season of stories from the mathematical domain! You can watch a video of animated Samuel telling you about the project, listen to Samuel speaking about why you should support this, or read an interview Samuel did about Relatively Prime with Shecky Riemann at Math-Frolic. To drum up your enthusiasm, you can listen to existing episodes or read our own Colin Beveridge’s recaps of season 2. Don’t delay too long, though – go to Kickstarter and pledge to support the project now!