Gabriel Nivasch @gnivasch@mathstodon.xyz

Consider the algorithm "M(x): if x<0 return -x, else return M(x-M(x-1))/2". This algorithm terminates for all real x, though this is not so easy to prove. In fact, Peano Arithmetic cannot prove the statement "M(x) terminates for all natural x". Paper to come! Joint work with @jeffgerickson and @alreadydone

...it also works with random points

These are the self-intersecting onions @jeffgerickson was mentioning

Any idea anyone?
https://mathoverflow.net/questions/338674/properties-of-the-affine-curve-shortening-flow

https://cstheory.stackexchange.com/questions/43832/