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Tag Archives: arithmetic
The wizard’s rational puzzle (solutions, part 2)
At long last, here is the solution I had in mind for the Wizard’s rational puzzle. Recall that the goal is to figure out the numerator and denominator of a secret rational number, if all we are allowed to do … Continue reading
Posted in arithmetic, challenges, logic, programming, puzzles, solutions
Tagged arithmetic, binary, denominator, Euclidean, gcd, logarithm, numerator, puzzle, rational, search, wizard
Comments Off on The wizard’s rational puzzle (solutions, part 2)
The wizard’s rational puzzle (solutions, part 1)
About two and a half months ago I posted a challenge involving a sadistic math wizard, metal cubes containing rational numbers, and a room full of strange machines. I’ve been remiss in following up with some solutions. (Go read the … Continue reading
Posted in arithmetic, challenges, logic, programming, puzzles, solutions
Tagged arithmetic, denominator, Euclidean, gcd, logarithm, numerator, puzzle, rational, wizard
3 Comments
The wizard’s rational puzzle (mind your p’s and q’s!)
You have been abducted by a sadistic math wizard (don’t you hate it when that happens?). He ushers you into a plain but cozylooking room, with a hardwood floor, a few exoticlooking rugs, and wood paneling on the walls. He … Continue reading
Posted in arithmetic, challenges, logic, programming, puzzles
Tagged arithmetic, denominator, numerator, puzzle, rational, wizard
15 Comments
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