

Young Alan Turing and the Arctangent - octonion
http://angrystatistician.blogspot.com/2015/01/young-alan-turing.html

======
tempodox
What is “ _undercontrained_ ”?

~~~
Pitarou
He means "underconstrained".

In other words, there is more than one function that satisfies the relation
f(2x) = f(x) * f(x), so we need to find some more constraints to exactly pin
down the Maclaurin expansion of exp(x).

------
kranner
The author seems to have linked to the wrong book as the inspiration for the
movie though the author's name is correct.

This is the book I remember seeing named in the credits:
[http://www.amazon.com/Alan-Turing-Enigma-Inspired-
Imitation-...](http://www.amazon.com/Alan-Turing-Enigma-Inspired-Imitation-
ebook/dp/B00M032W92/)

