Def onto == f:'a'b. onto('a;'b;f)

is mentioned by

Thm* equal(suc_rep,select(f:hind  hind. and(one_one(f),not(onto(f)))))

[hsuc_rep_def]

In prior sections: hol bool

Try larger context: HOLlib IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html