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# Monthly Archives: December 2015

## Link: Chat Noir

Just a link for you today: Chat Noir is a fun game where you try to trap a cat before it escapes. It’s quite mathematical, too. Can you figure out strategies for trapping the cat? Can you always win, or … Continue reading

## I made a Straws Thingy!

I finished my Straws Thingy! (You can see bigger versions of all the photos here.) It’s made out of 60 straws, 12 of each color. Three straws make a triangle; four triangles of each color are woven into a tetrahedron; … Continue reading

## Making stuff!

Recently I have been on a sort of kick making physical mathematical objects. First, inspired by this post on mathcraft.wonderhowto.com, I’ve learned how to fold origami Sonobe units and assemble them into various polyhedral things. So far, I’ve made a … Continue reading

## Book review: Alice’s Adventures in Wonderland

Alice’s Adventures in Wonderland: 150th Anniversary Edition Lewis Carroll Illustrated by Salvador Dalí Edited by Mark Burstein Princeton University Press, 2015 Recently Princeton University Press kindly sent me a review copy of Alice’s Adventures in Wonderland, recently republished in a … Continue reading

## MaBloWriMo 30: Cyclic subgroups

Today, to wrap things up, we will use Lagrange’s Theorem to prove that if is an element of the group , the order of evenly divides the order of . So we have a group and an element . In … Continue reading

Posted in algebra, group theory, proof
Tagged cyclic, groups, Lagrange, MaBloWriMo, proof, subgroups
6 Comments