Goldbach’s Conjecture

Sums of two primes

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Goldbach: every even number > 2 is a sum of two primes (unproved).
• Verified up to 4 × 10¹⁸.
• The weak version (three primes for odd numbers) was proved in 2013.

Steps

1. A letter from 1742
2. Count the ways
3. Goldbach’s comet
4. No room for 2
5. A hundred
6. Weak Goldbach