Roula Khalaf, Editor of the FT, selects her favourite stories in this weekly newsletter. “There is no such thing as an innocent map,” observes Philippe Rekacewicz in his catalogue essay that ...

Divided by 2m will make the Collatz Conjecture get a result of 1 for any positive integer. Also, the Collatz Tree showed that for any odd positive number, there is only one route existing in the ...