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### Meta

# Category Archives: group theory

## Stars of the Mind’s Sky with Diagrams

A few weeks ago, Paul Salomon posted a really beautiful work of mathematical art on his blog, Lost In Recursion: Stars of the Mind’s Sky, by Paul Salomon He included a precise mathematical description of the image, and I naturally … Continue reading

Posted in geometry, group theory, pictures, programming
Tagged art, diagrams, Haskell, polygon, star, visualization
9 Comments

## Searchable tiling database

Just a link today—check out this awesome tiling database! It’s got tons of beautiful plane tilings (with information and further reading about each one) and many ways to search through the database. It’s a great way to find examples of … Continue reading

## More on repetend lengths

In a previous post, I noted that the length of the repetend (repeating portion of the decimal expansion) of a fraction with prime denominator p is at most p-1, and in fact divides p-1. I also said: In fact, there’s … Continue reading

Posted in group theory, number theory, pattern, primes
Tagged decimal, expansion, fractions, length, repetend
6 Comments