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Category Archives: people
More on Human Randomness
In a post a few months ago I asked whether there is a way for a human to reliably generate truly random numbers. I got a lot of great responses and I think it’s worth summarizing them here! Randomness in … Continue reading
Human Randomness
Randomness is hard for humans It is notoriously difficult for humans to come up with truly random numbers. I don’t really have any data I can point to in particular, but there are quite a few well-known phenomena that show … Continue reading
Fibonacci’s Problem of the Birds
I have been enjoying reading Keith Devlin’s new book, Finding Fibonacci. I’ll write more about the book later. For now, I just wanted to share a nice problem I learned about which Leonardo Pisano, aka Fibonacci, included in his book … Continue reading
Book review: Genius at Play
Back in January I mentioned that I had been enjoying Siobhan Roberts’s new biography, Genius at Play: The Curious Mind of John Horton Conway. I finally finished it, and can now officially say that I really enjoyed it. This is … Continue reading
17×17 4-coloring with no monochromatic rectangles
Quick, what’s special about the following picture? As just announced by Bill Gasarch, this is a grid which has been four-colored (that is, each point in the grid has been assigned one of four colors) in such a way that … Continue reading
Posted in open problems, pattern, people, pictures
Tagged 17x17, four-coloring, graph, grid, monochromatic, rectangles
5 Comments
Herbert Wilf: 13 June 1931 – 7 January 2012
I was sad to learn that Herbert Wilf died yesterday. Long-time readers of this blog may remember him as one of the discoverers of the Calkin-Wilf tree, which I wrote about in a ten-part series of posts (1, 2, 3, … Continue reading
Book review: Magical Mathematics
Occasionally someone from Princeton University Press sends me a list of upcoming titles and asks if there are any I’d like to review. I jumped when I saw this one: a book about magic tricks and math! By Persi Diaconis … Continue reading
The wonderful world of Mike Reilly
The other day I received an email from Mike Reilly, who introduced himself as a professional game and puzzle inventor, and suggested that I might be interested in taking a look at a few of his web sites. I wasn’t … Continue reading
Vi Hart's math doodles
Vi Hart’s math doodle videos have been making the rounds of the math blogosphere (I heard of them from Denise at Let’s Play Math!). There are four videos so far and they are well worth watching — inspirational, creative, full … Continue reading