Some definitions of interest.
eq_int	Def i=j == if i=j true ; false fi
	Thm* i,j:. (i=j)
int_upper	Def {i...} == {j:| ij }
	Thm* n:. {n...}  Type
nat	Def  == {i:| 0i }
	Thm*   Type

About: IF YOU CAN SEE THIS go to /sfa/Nuprl/Shared/Xindentation_hack_doc.html