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# Monthly Archives: February 2008

## Recounting the Rationals, part IVb: the Euclidean Algorithm

Suppose we have two integers, and we’d like to find their greatest common divisor (GCD). Recall that the greatest common divisor of two integers m and n is exactly that: the greatest integer which is a divisor of both m … Continue reading

Posted in computation, iteration, number theory
15 Comments

## Recounting the Rationals, part IV

Continuing a series about the Calkin-Wilf tree (see those links for some background), today I’d like to show why all the rationals in the tree must be in lowest terms. Let’s start off with a little number theory! What do … Continue reading

Posted in induction, number theory, pattern, proof
11 Comments