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# Category Archives: links

## More on sums of palindromes

In my previous post I reported on a recent proof that every positive integer can be written as the sum of three palindromes. The first thing to report in this follow-up post is that Lewis Baxter sent me the Python … Continue reading

## Every positive integer is a sum of three palindromes

I recently learned from John Cook about a new paper by Javier Cilleruelo, Florian Luca, and Lewis Baxter proving that every positive integer can be written as a sum of three palindromes. A palindrome is a number that is the … Continue reading

Posted in arithmetic, computation, links
Tagged algorithm, constructive, news, palindromes, proof, sum
14 Comments

## Curvahedra

Everyone should go check out this Kickstarter project for CURVAHEDRA, a sort of construction kit that lets you build beautiful stuff like this: So cool! You can read more about the math behind them here. These are designed by Edmund … Continue reading

Posted in geometry, links
Tagged construction, Curvahedra, Kickstarter, polyhedra

## Network reliability

Over on my other blog I’ve started writing about an interesting but apparently nontrivial problem, which some readers of this blog may find interesting as well. Suppose you have a network of computers with some one-directional wires between them. Each … Continue reading

## 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

## Cosmic Call at The Universe of Discourse

I’ve really been enjoying a series of posts by Mark Dominus on his blog, The Universe of Discourse. The Cosmic Call was a series of radio messages sent in 1999 and 2003 aimed at various nearby stars (in case there … Continue reading