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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 upperleft 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, CalkinWilf, 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