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Prime Wisdom

A collection of educational, whimsical, and entirely prime observations.

Composite Numbers: The Team Players

If primes are the loners of the number world, composites are the social butterflies — every one of them a product of smaller friends working together.

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Euclid's Greatest Hit: Book IX, Proposition 20

In 300 BC, a Greek mathematician proved primes never run out — with an argument so clean it still makes people smile.

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From Name to Fingerprint

How we turn your name into a unique, one-way fingerprint (a hash) that nobody can reverse.

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How Decoding Works (Backwards Magic)

Given a prime and a tiny key, we can recover the original name. Here's exactly how the puzzle runs in reverse.

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How We Pack Your Name Into Fewer Bits

A clever 1952 compression trick lets us squeeze a name into a fraction of the space — and that's what makes finding your prime feasible.

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How We Tidy Your Name

How we turn your name into one consistent recipe for your prime — and how accents work in different algorithm versions.

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How We Tidy Your Name for the Puzzle

Before your name becomes a prime, it goes through a tiny grooming routine. Here's why, and what it does.

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Huffman Coding: Squeezing Names into Fewer Bits

How a 1952 idea by a graduate student lets us pack a name into 60 bits instead of 200 — and why a3.0 primes can be reversed.

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The Largest Known Prime

The record prime has over 41 million digits — 2^136279841 − 1, found by GIMPS in October 2024.

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Mersenne Primes: The Celebrity Primes

Primes of the form 2ⁿ − 1 are rare, enormous, and famous. They've been hunted for four centuries — and the search is still on.

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Organic, Artisanal Math

Why we use deterministic algorithms instead of AI to verify your prime — and why that matters more than you'd think.

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Pebbles and Primes

A hands-on pebble activity for discovering primes and multiplication by arranging stones in rows.

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Prime Hunting With Tiny Tweaks

How we wiggle a few free bits inside your puzzle until the whole thing happens to be a prime number.

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The Majesty of Numbers: Finding Your Prime

How we turn a name into a 128-bit digital signature that's yours and yours alone.

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Safe Primes: The Bodyguards of Cryptography

A safe prime is a prime where (p − 1) / 2 is also prime. They keep your secrets safe — literally.

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Share the Prime, Protect the Key

Your prime is a number you can show the world. Your key is the secret that turns it back into a name. Here's how to handle both.

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The Sieve of Eratosthenes

A 2,200-year-old algorithm for finding primes that's so simple a child can do it — and so clever it's still taught in every CS course.

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The Loneliness of the Number Two

Why the only even prime is basically the oddest number of all.

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The Miller–Rabin Test

How we know a number is prime without dividing by zillions of smaller numbers — the clever test behind your prime.

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The Nine Trick: How to Read Minds with a Calculator

A pocket-sized math trick that looks like magic — and the surprisingly simple secret that makes it work.

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The Prime Hunt

How we start at your number and step forward (odd numbers only) until we find the first prime — yours.

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Twin Primes: The Buddy System

Some primes travel in pairs, always exactly two apart. Nobody can prove they go on forever — but everybody believes it.

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What Do You Mean 1 Isn't Prime?

It looks prime, it feels prime, and for centuries mathematicians agreed. So what happened?

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Why Seven is Always Watching You

The mysterious, lucky, and slightly unsettling nature of the digit 7.

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Your Number in the Number Universe

What 128 bits means in friendly terms, and how your fingerprint becomes a starting point on a giant number line.

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Your Tiny Key and the Number Lock

Every a3.0 prime comes with a 3-character key. Here's what it does, why it's so short, and what kind of lock it's actually opening.

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