Today is International Women’s Day, so we’ve taken a moment to think about the woman mathematicians in our lives.

We each have fairly sizeable collections of maths books, which prompted CLP to wonder how many of them are by female authors. A quick scan of our respective bookshelves later, here’s what we found.

“Life moves very fast. It rushes from Heaven to Hell in a matter of seconds.”
― Paulo Coelho

This week, I was suddenly reminded of a fact I’d been meaning to keep track of, and I was disappointed to discover that even though I always endeavour to remember birthdays and holidays (mainly due to a system of elaborate reminders, notes and excessive list-making), I’d missed a hugely significant anniversary. Shortly after the clock struck midnight on New Year’s eve, I had passed one billion seconds old.

… if $B_1$, $B_2$, $\ldots$, $B_n$ are $n$ bases of an $n$-dimensional vector space $V$ (not necessarily distinct or disjoint), then there exists an $n \times n$ grid of vectors ($v_{ij}$) such that

1. the $n$ vectors in row $i$ are the members of the $i$th basis $B_i$ (in some order), and

2. in each column of the matrix, the $n$ vectors in that column form a basis of $V$.

Fan of the site Ravi Fernando has written in to tell us about his high score at the “is this prime?” game: a cool century!

I’ve been a fan of your “Is this prime?” game for a while, and after seeing your blog post from last May, I thought I’d say hi and send you some high scores. Until recently, my record was 89 numbers (last March 12), which I think may be the dot in the top right of your “human scores” graph. But I tried playing some more a couple weeks ago, and I found I can go a little faster using my computer’s y/n buttons instead of my phone’s touch screen. It turns out 100 numbers is possible!

Watch in amazement:

But, to the delight of prime fans everywhere, he didn’t stop there:

Today I even got 107 – good to have a prime record again.

Well done, Ravi!

Now is a good time to point out that the data on every attempt ever made at the game is available to download, in case you want to do your own analysis: at time of writing, there have been over 625,000 attempts, and 51 is still the number that catches people out the most.

It was George Boole’s bicentenary in 2015, so the Heslam Trust is a bit slow to reveal its plans to erect a statue of the great man in his home town of Lincoln.

There’s already a bust of Boole in University College, Cork, installed in plenty of time for the bicentenary. Here’s a picture of me and HRH Poppy Dog standing next to it, last Summer.

Why should I worry about dying? It’s not going to happen in my lifetime!

Raymond Smullyan, This Book Needs No Title (1986)

This week, the mathematical community has lost not one but two of its most beloved practitioners. Earlier this week, Swedish statistician Hans Rosling passed away aged 68, and today it’s been announced that author and logician Raymond Smullyan has also died, aged 97.