Abakcus

A simple succulent, but with pleasing geometry.

“Escher! Get your ass up here!”

Math doing math things.

A beautiful visual proof.

Math family.

Take a number made only of ones — a repunit — and square it. Out tumbles a perfect palindrome that climbs up to the count of ones and then walks right back down. The staircase holds beautifully up to nine ones; beyond that the digits begin to carry and the mirror finally cracks.

Dudeney Numbers. Only six positive integers share this curious property: each is a perfect cube whose digits, added up, bring you right back to the cube's root. They are 1, 8, 17, 18, 26, and 27 — and no seventh such number exists.

In English, the name of every single odd number contains the letter e.

Agnes Denes' beautiful visual mathematics.

Walk along the Fibonacci numbers as far as you like and you will never again land on a perfect square once you pass 144. Beyond the trivial 1, it is the only large Fibonacci number that is also a square — a fact proven by John H. E. Cohn in 1964. Fittingly, 144 sits at position twelve and equals twelve squared.

Write down the first 38 digits of π — starting with the 3 and continuing through the decimals — and you get a 38-digit integer. Remarkably, that integer is prime.

25 Short Math Books You Can Finish in One Sitting. Every one of them under 200 pages. 👇👇👇 abakcus.com/book-lists/sho…

The Feynman Point. Deep in the decimal expansion of π, at the 762nd place, six nines appear in a row: 999999. The run is named after Richard Feynman, who joked that he would love to memorize π all the way to that spot — so he could rattle off the digits and finish with "…nine, nine, nine, nine, nine, nine, and so on."

"Blue Diatoms" by Adolf Schmidt. A 19th-century naturalist spent his whole life collecting microscopic algae, then drew them — printed in blue, they look like stained glass and mandalas. archive.org/details/verzei…

In 1964 C. P. Willans wrote down a single closed-form expression that returns the n-th prime number exactly. The formula is perfectly exact — and gloriously useless to compute — but it settles a quiet question: yes, such a formula exists.

Jastrow Illusion. A pretty interesting optical illusion. The two figures are the same size.

The Fourier Transform, explained in one sentence by Stuart Riffle.

Maurits Cornelis Escher. reddit.com/r/oddlysatisfy…

Fibonacci tree 😱

"A fractal is a way of seeing infinity." - Benoit Mandelbrot