### Interesting Esoterica Summation

I feel like it’s time to do another summary of my recent additions to the Interesting Esoterica collection.

A reminder of what it’s all about: every now and then I encounter a paper or a book or an article that grabs my interest but isn’t directly useful for anything. It might be about some niche sub-sub-subtopic I’ve never heard of, or it might talk about something old from a new angle, or it might just have a funny title. I put these things in my Interesting Esoterica collection on Mendeley.

In this post the titles are links to the original sources, and I try to add some interpretation or explanation of why I think each thing is interesting below the abstract.

### MATH PROBLEMS?

Maths in the City posted this on twitter:

In order to make a number we can call, we need both of $n=(10x)(13i^2)$ and $m=\frac{\sin(xy)}{2.362x}$ to be integers.

### Putting all the world’s water in buckets

Following this pair of tweets about water:

A bucket full of water contains more atoms than there are bucketfuls of water in the Atlantic Ocean

— The QI Elves (@qikipedia) February 5, 2012

.@qikipedia There are 10,000× more molecules per pint of water than pints of water on earth. (3×10^21 pints/earth vs 2×10^25 molecules/pint)

— Matt Parker (@standupmaths) February 5, 2012

The obvious question is, at what point are the two numbers the same? Or,

If you put all the Earth’s water into containers of the same size so that each container carries as many atoms of water as there are containers, how big is each container?

### Newcastle MathsJam January 2012 Recap

January’s MathsJam was a bit massive. It’s now a week later and I’ve only just gathered enough thoughts together to do this writeup.

There were nine of us this month, all but one of whom either maths students or lecturers. A major theme of the night was of professional mathematicians or nearly-professional mathematicians forgetting basic high-school methods. This led to quite an intense session of puzzling and proving.

Things didn’t start out that way, though. A few weeks ago I found the website of a mathematician in Illinois called Alan Schoen, and his page about Lominoes. They’re a pretty interesting set of shapes!

### How to get beautifully typeset maths on your blog

Lots of people have blogs where they talk about maths. Lots of these people just use plain text for mathematical notation which, while it gets the point across, isn’t as easy to read or as visually appealing as it could be.

MathJax lets you write LaTeX and get beautifully typeset mathematical notation. And it’s really really easy to set up: you just need to paste some code into the header of your blog’s theme. To make it really really really easy, I’ve written some very detailed instructions of what to do for each big blogging service. (If you’re reading this after I wrote it, which you definitely are, beware that the interfaces I describe may have changed, so the advice below might be inaccurate.