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# Author Archives: Brent

## Origami stellated icosahedron!

Continuing what I started in December, I finally finished making a stellated icosahedron out of 30 Sonobe units. Each Sonobe unit corresponds to an edge of the icosahedron, and interlocks with three others to give the whole thing a remarkable … Continue reading

Posted in geometry, group theory
Tagged icosahedron, making, objects, origami, sonobe, stellated
3 Comments

## Post without words #5, explained

If you stared for a while at the images in my previous post, you probably noticed some patterns, and maybe you even figured out some sort of rule or algorithm behind them. Commenter Yammatak expressed it as “You split it … Continue reading

Posted in pattern, pictures, posts without words, sequences, solutions
Tagged curve, Hilbert, Prouhet-Thue-Morse, sequence, space-filling, Thue-Morse
3 Comments

## M74207281 is prime!

I’m a bit late to the party, but the Great Internet Mersenne Prime Search has recently announced a newly verified prime number, , with a whopping 22,338,618 decimal digits! This is now the largest known prime number (though of course … Continue reading