Jay Norwood:
A problem with the previous brad measurement is that his solution creates a diamond of size 2n+1 for an input of n. Correcting the size input for brad's function call, and re-running, I get this. So the various solutions can have overhead computation time of 40x difference, depending on the implementation.
The task didn't ask for a computationally efficient solution :-) So you are measuring something that was not optimized for. So there's lot of variance.
Bye, bearophile