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# Monthly Archives: May 2016

## Factorization diagram cards!

I’ve designed a set of factorization diagram cards and had them actually printed. This is one of the first times in my life when I have caused Actual Physical Objects to be created (other than using a printer I guess) … Continue reading

Posted in arithmetic, counting, pattern, pictures, primes, teaching, video
Tagged cards, diagrams, factorization
5 Comments

## 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

## Tiny Polka Dot

I’m really excited about Tiny Polka Dot, a Kickstarter project producing a deck of colorful, mathy cards especially for young children—along with a list of games to play with the cards. I have a four-year-old and I’m sure he is … Continue reading

## Apollonian gaskets and Descartes’ Theorem

In my previous post, I explained a recursive procedure for drawing Apollonian gaskets. Given any three mutually tangent circles, there are exactly two other circles which are mutually tangent to all three (forming what we called a “kissing set”). This … Continue reading