reconsider E = succ D as non empty set ;
D in {D}
by TARSKI:def 1;
then reconsider S = D as Element of E by XBOOLE_0:def 3;
set R = { [S,<*d,S*>] where d is Element of D : d = d } ;
{ [S,<*d,S*>] where d is Element of D : d = d } c= [:E,(E * ):]
proof
let a be
set ;
TARSKI:def 3 ( not a in { [S,<*d,S*>] where d is Element of D : d = d } or a in [:E,(E * ):] )
assume
a in { [S,<*d,S*>] where d is Element of D : d = d }
;
a in [:E,(E * ):]
then consider d being
Element of
D such that A1:
a = [S,<*d,S*>]
and
d = d
;
reconsider d =
d as
Element of
E by XBOOLE_0:def 3;
a = [S,<*d,S*>]
by A1;
hence
a in [:E,(E * ):]
;
verum
end;
then reconsider R = { [S,<*d,S*>] where d is Element of D : d = d } as Relation of E,(E * ) ;
take
GrammarStr(# E,S,(R \/ {[S,(<*> E)]}) #)
; ( the carrier of GrammarStr(# E,S,(R \/ {[S,(<*> E)]}) #) = succ D & the InitialSym of GrammarStr(# E,S,(R \/ {[S,(<*> E)]}) #) = D & the Rules of GrammarStr(# E,S,(R \/ {[S,(<*> E)]}) #) = { [D,<*d,D*>] where d is Element of D : d = d } \/ {[D,{} ]} )
thus
( the carrier of GrammarStr(# E,S,(R \/ {[S,(<*> E)]}) #) = succ D & the InitialSym of GrammarStr(# E,S,(R \/ {[S,(<*> E)]}) #) = D & the Rules of GrammarStr(# E,S,(R \/ {[S,(<*> E)]}) #) = { [D,<*d,D*>] where d is Element of D : d = d } \/ {[D,{} ]} )
; verum