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# Tag Archives: arithmetic

## More fun with Dirichlet convolution

I’m back after a bit of a hiatus for the holidays! Last time we saw how the principle of Möbius inversion arises from considering the function from the point of view of Dirichlet convolution. Put simply, the Möbius function is … Continue reading

Posted in number theory
Tagged arithmetic, convolution, Dirichlet, divisors, inversion, moebius, mu
1 Comment

## Right answers for the wrong reasons

Here’s a recent xkcd which as a math educator I found particularly funny. Some questions for my readers: What numbers besides 3 and 9 would “work” here? Do you have any particularly funny or interesting stories of students getting something … Continue reading

## minim

A fun game I discovered recently, minim. In each level you start out with a network of numbered nodes, and the object is to successively combine the nodes according to certain mathematical rules in order to end up with only … Continue reading