let s be State of SCM+FSA ; for I, J being Program of SCM+FSA
for a being read-write Int-Location st s . a > 0 & J is_closed_on s & J is_halting_on s holds
( if<0 a,I,J is_closed_on s & if<0 a,I,J is_halting_on s )
let I, J be Program of SCM+FSA ; for a being read-write Int-Location st s . a > 0 & J is_closed_on s & J is_halting_on s holds
( if<0 a,I,J is_closed_on s & if<0 a,I,J is_halting_on s )
let a be read-write Int-Location ; ( s . a > 0 & J is_closed_on s & J is_halting_on s implies ( if<0 a,I,J is_closed_on s & if<0 a,I,J is_halting_on s ) )
assume A1:
s . a > 0
; ( not J is_closed_on s or not J is_halting_on s or ( if<0 a,I,J is_closed_on s & if<0 a,I,J is_halting_on s ) )
assume that
A2:
J is_closed_on s
and
A3:
J is_halting_on s
; ( if<0 a,I,J is_closed_on s & if<0 a,I,J is_halting_on s )
A4:
if>0 a,J,I is_halting_on s
by A1, A2, A3, Th22;
if>0 a,J,I is_closed_on s
by A1, A2, A3, Th22;
hence
( if<0 a,I,J is_closed_on s & if<0 a,I,J is_halting_on s )
by A1, A4, Th18; verum