User blog comment:Wythagoras/All my stuff/@comment-5029411-20140111003502

Up to \(\vartheta(\Omega^{\Omega^\omega})\)

Y(6) rules +

a$(0,0...0,0,b+1 #) = a$(0,0...0,(0,0...0,...(0,0...0,(0,0...0,0,b #),b #)...,b #),b #) (a nested)