User blog comment:Simplicityaboveall/The Construction of Extremely Large Numbers/@comment-25337554-20160724103007

Your last number completely depends on the R function. For example, what is R_10^w(10^11)? It can't be neither w^e_0 ot e_0^w. If you say R function supports all the ordinals, your function will eventually go faster than any other computable function... As big as w_1^CK.