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Relatively Prime is back!

Aperiodipal numero uno Samuel Hansen’s acclaimed podcast series Relatively Prime is back, on a new monthly schedule, with an episode about how PhD student Ibrahim Sharif designed a lottery to award licences to sell cannabis in the state of Washington.

When the stakes are so high (geddit?! – Ed.) you have to be really sure that your lottery is fair. That’s where a lot of fun maths comes in.

You can listen to Lottery Daze on Sam intends to fund this new incarnation of Relatively Prime through Patreon – you can pledge to pay Sam a certain amount (starting at a dollar) for every episode he releases, with perks for paying more such as a postcard from Sam or placing an ad in one of the episodes.

Listen to Lottery Daze on

Support Relatively Prime on Patreon

Association for Women in Maths essay contest

The Association for Women in Mathematics in the USA is running its annual essay contest again, open to students in three age categories from Grade 6 to undergraduate.

Here’s the blurb:

To increase awareness of women’s ongoing contributions to the mathematical sciences, the Association for Women in Mathematics (AWM) and Math for America are co-sponsoring an essay contest for biographies of contemporary women mathematicians and statisticians in academic, industrial, and government careers.

The essays will be based primarily on an interview with a woman currently working in a mathematical sciences career. This contest is open to students in the following categories: Grades 6-8, Grades 9-12, and College Undergraduate. At least one winning submission will be chosen from each category. Winners will receive a prize, and their essays will be published online at the AWM web site. Additionally, a grand prize winner will have his or her submission published in the AWM Newsletter.

The deadline for entries is January the 31st 2017, and if you want the AWM to pair you up with an interviewee, you need to get a request in by January 10th.

All the prize-winning essays from previous years are online, including this nice one about Tanya Khovanova by high school student Emily Jia.

More information

AWM essay contest

Contest rules

Past winners

Apéryodical takeover: It’s Roger Apéry’s 100th birthday!


Today is the 100th anniversary of Roger Apéry’s birth, and we’re The Aperiodical, so we just had to make a big deal of it.

So, for all of today, we’re The Apéryodical. Throughout today we’ve got a few posts about Apéry and the thing he’s most closely associated with: the Riemann zeta function.

For now, here’s a really big ζ. You’ll need it later.


Not Mentioned on the Aperiodical, 10th November 2016

Here’s a round-up of some of the news from this month.

Never-ending Turing centenary, part XLVI

The Alan Turing centenary shows no signs of abating.

First of all, there’s a marvellous new art installation under Paddington Bridge in London, in memory of Turing. There’s also a theatre piece called Breaking the Code, showing at Manchester’s Royal Exchange Theatre until 19th November.

Secondly, work continues to introduce legislation in the UK pardoning all gay men who were convicted of crimes related to homosexuality, in the same way Alan was a few years ago. Ministers said they were ‘committed’ to getting the law passed, but in an emotional session the bill was “talked out” by minister Sam Gyimah, meaning it wasn’t voted on.

LMS wins the first Royal Society Athena prize

The London Mathematical Society (LMS) has been honoured this autumn by receiving the first Royal Society Athena Prize to recognise its advancement of diversity in science, technology, engineering and mathematics (STEM) within the mathematical community. The prize was awarded in a ceremony at the Royal Society’s annual diversity conference on 31 October.

Royal Society press release

Fourth Christopher Zeeman medal goes to Rob Eastaway

Mathematician, author and friend of the site Rob Eastaway has received the 2016 Christopher Zeeman medal, awarded to recognise and acknowledge the contributions of mathematicians involved in promoting mathematics to the public and engaging with the public in mathematics in the UK.

There will be an award lecture taking place on 22 March 2017, and details will be announced in Mathematics Today and the LMS Newsletter.

IMA website article on the award
Rob Eastaway’s citation (PDF)

The magic number 25641

Reader of the site Bhaskar Hari Phadke has written in to tell us this fun fact about the number $25641$. It’s easier to show than to describe, so here goes:

25641 \times \color{blue}{1} \times 4 &= \color{blue}{1}02564 \\
25641 \times \color{blue}{2} \times 4 &= \color{blue}{2}05128 \\
25641 \times \color{blue}{3} \times 4 &= \color{blue}{3}07692 \\
25641 \times \color{blue}{4} \times 4 &= \color{blue}{4}10256 \\
25641 \times \color{blue}{5} \times 4 &= \color{blue}{5}12820 \\
25641 \times \color{blue}{6} \times 4 &= \color{blue}{6}15384 \\
25641 \times \color{blue}{7} \times 4 &= \color{blue}{7}17948 \\
25641 \times \color{blue}{8} \times 4 &= \color{blue}{8}20512 \\
25641 \times \color{blue}{9} \times 4 &= \color{blue}{9}23076

A good one to challenge a young person with.

I did a little bit of Sloanewhacking and found a couple of sequences containing $25641$ which almost, but don’t quite, describe this property. So, semi-spoiler warning: you might enjoy A256005 and A218857. I’d like to come up with the ‘magic number’ which looks the least like it’ll have this property – any ideas?

Thanks, Bhaskar!