Rather by accident I've noticed that the following trivial code produces different output in Mathematica 9 and 10:
-((-1)^n)
Mathematica 9:
$-(-1)^n$
Mathematica 10:
$(-1)^{(n+1)}$
Both forms are of course correct, but this a bit annoying if one uses the same set of unit tests to check the code against both versions. Can someone confirm this? Does someone know the reasoning behind this change?
