Category Archives: numbers

the heart of mathematics

2-3-5-7-11

Posted on 24/08/2011 by

Yesterday, my friend and ex-colleague Dan Hughes emailed a group of his friends to explain that he had established that earth had been visited in antiquity by alien group theorists. How else to explain that the number of minutes in … Continue reading →

Posted in exposition, numbers | Tagged , | 1 Comment

Numbers Farm

Posted on 30/12/2010 by

In Kings Langley, just north-west of London on the Grand Union Canal, behind the railway station you will find Numbers Farm. What crops do they grow there? Here are some of the staples: In the further-flung fields you find more … Continue reading →

Posted in geography, numbers | Leave a comment

Large numbers

Posted on 28/05/2010 by

Littlewood published an article entitled “Large numbers” in the Mathematical Gazette in 1948. One of his examples depends on his own theorem about the relation between π(x) (the number of primes up to x) and li(x) (the integral of 1/log t … Continue reading →

Posted in exposition, numbers, open problems | 3 Comments

The symmetric group, 1

Posted on 30/04/2010 by

This is the first of a short series of posts which will try to look at the symmetric group in slightly fresh ways. It is in part a fraternal greeting to my friends on SymOmega, who named their blog after … Continue reading →

Posted in books, exposition, numbers, symmetric group | 8 Comments

Counting

Posted on 04/02/2010 by

I’m teaching enumerative combinatorics this term; it brings an old incident back to my mind. In 1984, Dugald Macpherson and I stopped for breakfast at a Dutch pancake house near Vancouver. The restaurant offered a choice of “1001 toppings”. We … Continue reading →

Posted in books, exposition, numbers | 3 Comments