Math · 3
In 2013, mathematician Harald Helfgott proved that every odd number greater than 5 can be written as the sum of how many prime numbers?
Answer
Three primes
Helfgott's 2013 proof resolved the 'weak' Goldbach conjecture, showing every odd number greater than 5 is the sum of three primes, a result distinct from the still-unproven conjecture about even numbers and two primes.
💡 Did you know?
Every even number greater than 2 can be expressed as the sum of two primes, yet Goldbach's Conjecture remains unproven despite verification for trillions of cases.
Other options people guess
- Two primes
- Four primes
- Five primes
Topics
- prime-numbers
- number-theory
- goldbach
- conjecture
Know your math trivia?
Play a free Math quiz and see how many you get right — no signup needed to start.
More Math facts
Math
Which 18th-century female mathematician corresponded with Carl Friedrich Gauss under the male pseudonym 'Monsieur LeBlanc'?
Sophie Germain proved theorems under a man's pseudonym so she could study mathematics—her real identity wasn't fully recognized until after her death.
Math
What is the status of the Collatz Conjecture as of the early 21st century?
The Collatz Conjecture—propose any number, halve if even or triple-and-add-one if odd, repeat—remains unsolved despite its child-simple description.
Math
Which organization established the million-dollar reward that still awaits a proof of the Riemann Hypothesis?
A $1 million Clay Prize awaits anyone solving the Riemann Hypothesis, yet many top mathematicians avoid it, fearing decades of futility.
Math
Who invented the equals sign (=) in 1557?
The equals sign (=) didn't exist until 1557 when Robert Recorde invented it—mathematicians literally wrote out 'is equal to' before then.
Math
In the Birthday Paradox, how many people must be in a room for there to be roughly a 50% chance that two share a birthday?
Birthday Paradox reveals only 23 people needed in a room for 50% odds two share a birthday—our brains wildly underestimate how fast probabilities compound.
Math
Centuries before Fibonacci, Indian mathematicians arrived at the same numerical sequence while analyzing patterns in what field of study?
Fibonacci introduced his sequence to Europe through a problem about rabbit breeding in 1202, but the pattern had been discovered by Indian mathematicians centuries earlier.