IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html
At:
hsum iso def 'a,'b:S.
and
(all(a:hsum('a; 'b). equal(abs_sum(rep_sum(a)),a))
,all
,(r:hbool 'a'b hbool. equal
,(r:hbool 'a'b hbool. (is_sum_rep(r)
,(r:hbool 'a'b hbool. ,equal(rep_sum(abs_sum(r)),r))))