User blog comment:Googleaarex/Make an extension of the notation/@comment-5029411-20140926211035/@comment-25371339-20140927133257

Here is up arrow extension:

a-(-) ^^^ ---b = a-(-)^^ (-) ^^ (-) ^^...^^ (-) ^^ (-) ^^ (-)-a with b levels

a-(-) ^^^ - ^^^ ---b = a-(-) ^^^ (-) ^^ (-) ^^ (-) ^^...^^ (-) ^^ (-) ^^ (-)-a with b levels

a-(-) ^^^^ ---b = a-(-)^^^ (-) ^^^ (-) ^^^ ... ^^^ (-) ^^^ (-) ^^^ (-)-a with b levels

etc.

Limit is a-(-) ^^^...^^^ ---b