Concept

Primes

3 essays name this object, across one field. What follows is each of them, and the objects they name alongside it.

Pascal's triangle, in two colours

Shade the odd numbers in Pascal's triangle and a fractal appears. Nothing was designed to produce it, and the same shape arrives independently from a completely different construction.

discrete · pascals triangle

The primes on a spiral, and a pattern nobody ordered

Wind the whole numbers outward in a square spiral, mark the primes, and they line up on diagonals. The observation is a hundred years old and there is still no proof it means anything.

discrete · prime distribution

Numbers that wrap

A clock does arithmetic. It has finitely many numbers, addition never leaves it, and multiplication behaves entirely differently depending on one property of the size of the dial.

discrete · modular arithmetic

Named alongside it

The objects these essays reach for when they reach for this one.

Parity Binomial coefficient Conjecture Cramér's model Cyclic group Fermats little theorem Greatest common divisor Kummer's theorem Lucas' theorem Modular arithmetic Order Periodicity

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