Section RClo.
Inductive rclo3 (clo: rel->rel) (r: rel): rel :=
| rclo3_base
x0 x1 x2
(IN: r x0 x1 x2):
@rclo3 clo r x0 x1 x2
| rclo3_clo'
r' x0 x1 x2
(LE: r' <3= rclo3 clo r)
(IN: clo r' x0 x1 x2):
@rclo3 clo r x0 x1 x2
.

Lemma rclo3_mon_gen clo clo' r r' x0 x1 x2
(IN: @rclo3 clo r x0 x1 x2)
(LEclo: clo <4= clo')
(LEr: r <3= r') :
@rclo3 clo' r' x0 x1 x2.