Prove:
(Lemma (0+)) ,
under the assumptions:
(Definition (+): 1) ,
(Definition (+): 2) .
We prove () by induction on .
Induction Base:
Induction Step:
•
![[Graphics:Images/index_gr_1.gif]](Images/index_gr_1.gif){kind=small}
,
![[Graphics:Images/index_gr_2.gif]](Images/index_gr_2.gif){kind=small}
,
![[Graphics:Images/index_gr_3.gif]](Images/index_gr_3.gif){kind=small}
.
![[Graphics:Images/index_gr_4.gif]](Images/index_gr_4.gif){kind=small}
) by induction on ![[Graphics:Images/index_gr_5.gif]](Images/index_gr_5.gif){kind=small}
.