User blog comment:Mush9/MUSH/@comment-27516045-20161008171408/@comment-29014792-20161012192936

I beat this:

U_0(X) = X-system with X symbols using any language. (Yes, that is illdefined)

Else U_a(b) uses the generalization of f_a(b).

U_w^CK_1(10^100).