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### Meta

# Category Archives: geometry

## Factorization diagram posters!

I’ve finally gotten around to making a nice factorization diagram poster: You can buy high-quality prints from Imagekind. (If you order soon you should have them before Christmas! =) I’m really quite happy with imagekind, the print quality is fantastic … Continue reading

Posted in arithmetic, counting, geometry, number theory, pattern, pictures, primes
Tagged diagrams, factorization, posters
7 Comments

## Making connections

Here’s something fun I was playing around with today. I generated 100 random points and connected some of them with lines. Can you figure out how I chose which lines to draw? How about these? (Same points, different lines.) Or … Continue reading

## Stars of the Mind’s Sky with Diagrams

A few weeks ago, Paul Salomon posted a really beautiful work of mathematical art on his blog, Lost In Recursion: Stars of the Mind’s Sky, by Paul Salomon He included a precise mathematical description of the image, and I naturally … Continue reading

Posted in geometry, group theory, pictures, programming
Tagged art, diagrams, Haskell, polygon, star, visualization
9 Comments

## Penrose tiles on my refrigerator!

I got some Penrose refrigerator magnets in the mail the other day! They look nice on my fridge, don’t you think? Here’s a close-up: (Unfortunately, since this was just a Kickstarter project there’s no way to order more at this … Continue reading

Posted in geometry, pattern, pictures
Tagged Kickstarter, magnet, penrose, refrigerator, tile
6 Comments

## Book review: Discrete and Computational Geometry

Discrete and Computational GeometrySatyan L. Devadoss & Joseph O’Rourke [Full disclosure: Princeton Press kindly sent me a free review copy of this book, and Satyan Devadoss is a (former) teacher and (current) good friend of mine. I was the TA … Continue reading

Posted in books, computation, geometry, pictures, review

## Searchable tiling database

Just a link today—check out this awesome tiling database! It’s got tons of beautiful plane tilings (with information and further reading about each one) and many ways to search through the database. It’s a great way to find examples of … Continue reading

## Book review: In Pursuit of the Traveling Salesman

As mathematical problems go, the “traveling salesman problem” (TSP) is a rare gem: it is simultaneously of great theoretical, historical, and practical interest. On the theoretical front, it is a well-known example of the class of “NP-complete” problems, which lie … Continue reading

Posted in books, computation, geometry, open problems, review
Tagged book review, salesman, TSP. traveling
6 Comments

## Dimensions: go watch! now!

I finally got around to watching the Dimensions videos, which I mentioned once before. They are super cool and will be sure to blow your mind! They start by explaining some simple tools (stereographic projection) and intuition (with references to … Continue reading

Posted in fractals, geometry, links, video
Tagged Dimensions, fibration, polytope, projection, video
2 Comments

## Book review: Viewpoints: Mathematical Perspective and Fractal Geometry in Art

This book is certainly quite different from the sort I usually read and review—but I am always interested in new and creative ways to teach mathematics! This is quite a fun book. It’s all about visual art and some of … Continue reading