let l be Element of NAT ; SUCC (l,SCMPDS) = NAT
thus
SUCC (l,SCMPDS) c= NAT
; XBOOLE_0:def 10 NAT c= SUCC (l,SCMPDS)
let x be object ; TARSKI:def 3 ( not x in NAT or x in SUCC (l,SCMPDS) )
set X = { ((NIC (i,l)) \ (JUMP i)) where i is Element of the InstructionsF of SCMPDS : verum } ;
assume
x in NAT
; x in SUCC (l,SCMPDS)
then reconsider x = x as Element of NAT ;
reconsider xx = x as Element of NAT ;
set i = goto (xx - l);
NIC ((goto (xx - l)),l) =
{|.((xx - l) + l).|}
by Th3
.=
{x}
by ABSVALUE:def 1
;
then A1:
x in (NIC ((goto (xx - l)),l)) \ (JUMP (goto (xx - l)))
by TARSKI:def 1;
(NIC ((goto (xx - l)),l)) \ (JUMP (goto (xx - l))) in { ((NIC (i,l)) \ (JUMP i)) where i is Element of the InstructionsF of SCMPDS : verum }
;
hence
x in SUCC (l,SCMPDS)
by A1, TARSKI:def 4; verum