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# Monthly Archives: January 2008

## Recounting the Rationals, part III

First, a quick recap: continuing an exposition of the paper Recounting the Rationals, we’re investigating the tree of fractions shown below (known as the Calkin-Wilf tree), which is constructed by placing 1/1 at the root node, and giving each node … Continue reading

Posted in number theory, pattern, proof, recursion
10 Comments

## Fun "mathemagic" video

For something on the lighter side, here’s a fun video that I’ve seen linked to from a number of places. It’s a video of Arthur Benjamin, a math professor at Harvey Mudd College, performing a fifteen-minute “mathemagics” show. He multiplies … Continue reading

Posted in computation, links, people, video
1 Comment

## Recounting the Rationals, part II (fractions grow on trees!)

Today I’d like to continue my exposition of the paper “Recounting the Rationals”, which I introduced in a previous post. Recall that our goal is to come up with a “nice” list of the positive rational numbers — where by … Continue reading

Posted in infinity, number theory, pattern, recursion, sequences
22 Comments