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# Category Archives: logic

## 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 cozy-looking room, with a hardwood floor, a few exotic-looking rugs, and wood paneling on the walls. He … Continue reading

Posted in arithmetic, challenges, logic, programming, puzzles
Tagged arithmetic, denominator, numerator, puzzle, rational, wizard
9 Comments

## Book review: Roads to Infinity

What is infinity? What is proof? These are two of the biggest questions mathematicians have grappled with over the years. In this well-written and fascinating book, John Stillwell takes us on a tour through some of the answers to these … Continue reading

Posted in arithmetic, books, computation, induction, infinity, logic, proof, review
Tagged infinity, John Stillwell, proof, roads

## Manufactoria

A friend of mine just pointed me to a most excellent puzzle game, Manufactoria, wherein you build little machines to test robots. For now I won’t give away the secret of what real math/computer science topic the game teaches you, … Continue reading

## The haybaler

At Penn Alexander’s math club yesterday, the students worked on a fun puzzle that I’d never seen before. It goes like this: You have five bales of hay. For some reason, instead of being weighed individually, they were weighed in … Continue reading

## Who Am I?

An excellent puzzle from JD2718: There are five true and five false statements about the secret number. Each pair of statements contains one true and one false statement. Find the trues, find the falses, and find the number. 1a. I … Continue reading

Posted in challenges, logic, number theory, puzzles, teaching
Tagged number, puzzle, secret
13 Comments

## Logicomix: An Epic Search for Truth

I recently acquired a copy of Logicomix: An Epic Search for Truth, by Apostolos Doxiadis and Christos Papadimitriou, with art by Alecos Papadatos and Annie Di Donna. It defies categorization: is it a comic book? A biography? A book of … Continue reading

Posted in books, logic, review
Tagged Bertrand Russell, book review, foundations, graphic novel, logic, philosophy, set theory
2 Comments