User blog comment:Hyp cos/Attempt of OCF up to Stability/@comment-31580368-20181029042115/@comment-11227630-20181029053331

sup{(x+a)-stable|a<λx.x-stable} is simply \(\psi_{S(1,0)}(,0)\).

There should be some way to use a (+)-stable ordinal as a diagonalizer, but I have not found the right way.