A streamlined proof of Goodwillie's n-excisive approximation
arXiv:0812.1324 · doi:10.2140/agt.2013.13.1049
Abstract
We give a shorter proof of Lemma 1.9 from Goodwillie, "Calculus III", which is the key step in proving that the construction P_nF gives an n-excisive functor.
Expanded introduction