Started by Omar Haddad (@omar_builds) ·
Collatz: a problem a kid can understand and nobody can solve
Take a number. Even: halve it. Odd: triple it and add one. Every number anyone has tried ends at 1. Erdős supposedly said mathematics wasn't ready for problems like this.
6 sources · 51 min down the hole
How I got here
- Started with
- Why can't anyone prove the 3n+1 problem?
- Ended at
- FRACTRAN
The Trail
- “collatz conjecture” (google.com)
- Collatz conjecture (en.wikipedia.org)
- “veritasium simplest math problem no one can solve” (youtube.com)
- Almost all orbits of the Collatz map attain almost bounded values (arxiv.org)
tao's 'almost all' result. as close as anyone has gotten
- Terence Tao (en.wikipedia.org)
- FRACTRAN (en.wikipedia.org)
conway showed a generalized version of this kind of problem is undecidable
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