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# Monthly Archives: October 2011

## Post without words #3

(This is my 200th post! =)

Posted in counting, pattern, pictures, posts without words, recursion
11 Comments

## More fun with infinite decadic numbers

This is the sixth in a series of posts on the decadic numbers (previous posts: A curiosity, An invitation to a funny number system, What does “close to” mean?, The decadic metric, Infinite decadic numbers). Last time I left you … Continue reading

Posted in arithmetic, infinity, number theory
Tagged decadic, decimal, fractions, integers, representation
4 Comments

## Book review: Magical Mathematics

Occasionally someone from Princeton University Press sends me a list of upcoming titles and asks if there are any I’d like to review. I jumped when I saw this one: a book about magic tricks and math! By Persi Diaconis … Continue reading

## Infinite decadic numbers

To recap: we’ve now defined the decadic metric on integers by where is not divisible by 10, and also . According to this metric, two numbers are close when their difference is decadically small. So, for example, and are at … Continue reading

Posted in arithmetic, convergence, infinity, number theory
Tagged decadic, negative, numbers
7 Comments