# Carnival of Mathematics 190

Welcome to the 190th Carnival of Mathematics! For those new to the Carnival, it is a monthly roundup of Mathematical blogging/video making/podcasting/activities. It’s coordinated by The Aperiodical where you can find links to all previous Carnivals. Every month, it is hosted by a different blog, and this month it is my turn!

It is traditional to begin the Carnival with facts about the number of the Carnival, and this Carnival shall be no different. Starting with non-Mathematical facts, the $190$ Bus in London goes from Richmond to Earl’s Court. 1-9-0 is the emergency telephone number in Brazil (a fact I hope that none of you ever have to use). One final non-mathematical fact is that General Dong Zhuo seized power in China in the year $190$ AD.

In terms of mathematical properties $190 = 2 \times 5 \times 19$. It has a digit sum of $10$, so it is divisible by its digit sum. $190$ is not only a triangle number, but also a hexagonal number. The sum of the number of vertices, edges, and faces of all the Platonic solids happens to be $190$ too (check for yourself if you don’t believe me!). In Roman numerals, $190$ is a palindrome (CXC) and it’s actually the largest palindrome who’s factors are all also palindromes when written in Roman numerals.

Let me know if you have any other favourite facts about $190$, but I know you’ll be itching to find out about this month’s content, and I won’t keep you waiting any longer!

First up, we have a fantastic new venture from the European Mathematical Society. The Pop Math website collects and shares Maths outreach events in Europe (and beyond). It was launched on the 21st January (the launch can be found here) and is well worth a look. I am personally so excited about this, and would recommend you take a look (and then keep checking it regularly!).

Some readers of mine may know that last summer I did an internship with Dr Tom Crawford (of TomRocksMaths fame) and am still releasing the podcasts I worked on during that. But I’m not the only intern Tom has had, and other TomRocksMaths interns have been busy this month! Amie Campbell produced this video with a neat solution to a probability puzzle. Lucas Bachmann has created this series of puzzles which are great for a coffee break. On Tom’s website you’ll also find links to some great videos he’s created himself.

In the theme of promoting people I’ve worked with, Chalkdust Magazine is accepting submissions for Issue 13 (which will be fantastic if the previous issues are anything to go by). Whilst I’m discussing Mathematical magazines, another Carnival favourite is Quanta Magazine and this month is no different. I loved this article by Stephen Ornes about steps being made to tackle Hilbert’s 13th problem.

As always, there have been some interesting Mathematical discussions on twitter. Kareem Carr gave this lovely explanation of “The Monty Problem”. I would like to draw your attention to this discussion thread on pandemic friendly learning enrichment activities, and also to this thread of Maths communicators/freelancers.

There was exciting news from the other side of the world, as Cheryl Praeger (Western Australia’s first female Maths professor) was made Companion of the Order of Australia. Peter Cameron writes about it here. Brady Haran (known for creating Numberphile was awarded the Medal of the Order of Australia.

Katrik (a favourite of the Carnival of Mathematics) has been bust as ever, and has recently written a blog post about finding tree fractals (and there are even some hearts, just in time for Valentine’s Day). This post is a personal favourite of mine as it combines some fun coding with cool Maths and there’s even a quote from one of my favourite plays!

Those familiar with the concept of protein folding will love Sabine Hossenfelder’s blog post and accompanying video on the subject. If, like me, it’s new to you then you’ll enjoy learning about a new (and very important!) application of Maths.

This has been very enjoyable but I’m going to end this Carnival with a call to action. Timothy Gowers is a Mathematician at Trinity College, Cambridge, where I also studied. Like me, he has a blog (but unlike me, he has a Fields Medal). He has recently taken to his blog to inform people of how Leicester University is planning on making its Pure Mathematics department redundant. On his blog you’ll find a link to a petition you can sign. Whilst you’re there, I’d recommend giving his other blog posts a read too!

It’s been a pleasure to host the 190th Carnival of Mathematics. Keep your eyes peeled on Sophia’s blog for the 191st edition.