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# Category Archives: posts without words

## Post without words #26

Posted in modular arithmetic, number theory, posts without words
Tagged Euler, grid, totient
2 Comments

## More words about PWW #25: The Chinese Remainder Theorem

In a previous post I made images like this: And then in the next post I explained how I made the images: starting in the upper left corner of a grid, put consecutive numbers along a diagonal line, wrapping around … Continue reading

Posted in modular arithmetic, number theory, posts without words
Tagged Chinese, grid, remainder, theorem, torus
3 Comments

## A few words about PWW #25

In my previous post I made images like this: What’s going on? Well, first, it’s easy to notice that each grid starts with in the upper-left square; is one square down and to the right of , then is one … Continue reading

Posted in modular arithmetic, number theory, posts without words
Tagged Chinese, grid, remainder, theorem, torus
4 Comments

## Fermat witnesses and liars (some words on PWW #24)

Let be a positive integer we want to test for primality, and suppose is some other positive integer with . There are then four possibilities: and could share a common factor. In this case we can find the common factor … Continue reading

Posted in computation, number theory, posts without words, primes
Tagged Fermat, liar, primality, test, witness
1 Comment

## Post without words #24

Posted in computation, number theory, posts without words, primes
Tagged Carmichael, Fermat, primality, test
5 Comments

## Post without words #23

Posted in pattern, pictures, posts without words
Tagged algorithm, Calkin-Wilf, Euclidean, tree
11 Comments

## Post without words #22

Posted in arithmetic, computation, number theory, posts without words
Tagged logarithmic, repeated, squaring
8 Comments

## Post without words #21

Posted in combinatorics, geometry, posts without words
Tagged enumeration, orthogonal, polygons
17 Comments

## From primitive roots to Euclid’s orchard

Commenter Snowball pointed out the similarity between Euclid’s Orchard… …and this picture of primitive roots I made a year ago: At first I didn’t see the connection, but Snowball was absolutely right. Once I understood it, I made this little … Continue reading