A streamlined proof of Goodwillie'sn–excisive approximation

Charles Rezk
2013 Algebraic and Geometric Topology  
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.
doi:10.2140/agt.2013.13.1049 fatcat:omfqo2pn7zd5hndnjzxbjfu6su