{c}
{title2=December 2025}

https://projecteuler.net/problem=973

Numerical solution:
``
427278142
``

Earliest known public leak:
* https://github.com/lucky-bai/projecteuler-solutions/issues/104

Programs:
* https://github.com/cirosantilli/project-euler-solvers/blob/master/solvers/973.py

Notes:
* https://matharena.ai/?comp=euler--euler from <MathArena> claims <Gemini 3> solved it
* https://x.com/roanoke_gal/status/1997322744594125081 claims <GPT-5.1 Pro> solved it.


Project Euler problem 973

{c}

This is the variant of <GPT-5.1> that you get on the web UI. It is unknown exactly how it correlates with the API.


Ciro Santilli @cirosantilli 40

 Incoming links: GPT-5.1 Pro