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# Category Archives: pictures

## Factorization diagram card redesign: feedback welcome!

After getting a printed set of factorization diagram cards, I decided there were a few design tweaks I wanted to make. I’ve gone through a few iterations and I think they are definitely better now. Here are some representative samples … Continue reading

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

## Post without words #8

Posted in geometry, pattern, pictures, posts without words
Tagged tessellation, units
Leave a comment

## Making tessellations

I just received my copy of Tessalation!, a great new book written by Emily Grosvenor and beautifully illustrated by Maima Widya Adiputri, which I helped fund on Kickstarter. It’s about a girl named Tessa who goes exploring in her backyard … Continue reading

Posted in books, geometry, pattern, pictures
Tagged blog, book, Tessalation, tessellation, tour, units
8 Comments

## Apollonian gaskets and Descartes’ Theorem II

In a few previous posts I wrote about “kissing sets” of four mutually tangent circles, and the fact that their signed bends satisfy Descartes’ Theorem, (Remember that the signed bend of a circle is like the curvature , except that … Continue reading