You may have seen our post last month about our remote Wiki Editing Day, this coming **Saturday 12th May**. We’re hoping to get a bunch of people in different locations editing pages on Wikiquote and other Wikimedia sites, to improve the visibility of female mathematicians. Here’s how you can get involved.

# You're reading: News

### The chromatic number of the plane is at least 5

A long-standing mathematical problem has had a recent breakthrough – scientist Aubrey de Grey has proved that the chromatic number of the plane is at least 5.

### Wikiquote edit-a-thon – Saturday, May 12th, 2018

**TL;DR:** We’re holding a distributed Wikipedia edit-a-thon on Saturday, May 12th, 2018 from 10am to improve the visibility of women mathematicians on the Wikiquotes Mathematics page. Join in from wherever you are! Details below, and in this Google Doc.

Extension and abstraction without apparent direction or purpose is fundamental to the discipline. Applicability is not the reason we work, and plenty that is not applicable contributes to the beauty and magnificence of our subject.

– Peter Rowlett, “The unplanned impact of mathematics”, Nature 475, 2011, pp. 166-169.Trying to solve real-world problems, researchers often discover that the tools they need were developed years, decades or even centuries earlier by mathematicians with no prospect of, or care for, applicability.

– Peter Rowlett, “The unplanned impact of mathematics”, Nature 475, 2011, pp. 166-169.There is no way to guarantee in advance what pure mathematics will later find application. We can only let the process of curiosity and abstraction take place, let mathematicians obsessively take results to their logical extremes, leaving relevance far behind, and wait to see which topics turn out to be extremely useful. If not, when the challenges of the future arrive, we won’t have the right piece of seemingly pointless mathematics to hand.

Peter Rowlett, “The unplanned impact of mathematics”, Nature 475, 2011, pp. 166-169.

Now, don’t get me wrong. I have every admiration for Peter and his work; his is a thoughtful voice of reason, and it’s not at all unreasonable for the Wikiquote page on mathematics to cite his writing.

### Hannah Fry’s ‘Contagion’ programme broadcast tonight

You may remember back in September we posted about a mass-participation science experiment, aiming to model the spread of diseases in human populations using a smartphone app. The results of this experiment, presented by the contagiously loveable Hannah Fry, will be presented in a documentary this evening on BBC4. You can also see Hannah chatting about the experiment on this evening’s The One Show.

Contagion! The BBC4 Pandemic, on the BBC watch-o-tron

### Abel Prize 2018

The Abel Prize for 2018 has been awarded to Robert Langlands, for his work on representation theory and number theory. The Abel Prize website has a page with more information, including a lay explanation of Langlands’ work by Alex Bellos.

Robert P. Langlands wins the 2018 Abel Prize “for his visionary program connecting representation theory to number theory.” Congratulations! pic.twitter.com/HBiTJhChe0

— AbelPrize (@abel_prize) March 20, 2018

### The OEIS now contains 300,000 integer sequences

The Online Encyclopedia of Integer Sequences just keeps on growing: at the end of last month it added its 300,000^{th} entry.

Especially round entry numbers are set aside for particularly nice sequences to mark the passing of major milestones in the encyclopedia’s size; this time, we have four nice sequences starting at A300000. These were sequences that were originally submitted with indexes in the high 200,000s but were bumped up to get the attention associated with passing this milestone.

### Proof by sedition

\[ n > 2 \]

An unexpected bit of controversy involving mathematical notation hit the internet last week, when China's government briefly blocked all Chinese internet users from viewing any page or message containing the letter *n*.

Apparently, those in charge of the Great Firewall feared that those who disapproved of Xi Jinping removing the two-term limit on his presidency of China would use the letter *n* to refer to the now-arbitrary number of terms for which he can remain in power.

There's some more context in a post by Victor Mair on Language Log, and in the Guardian.