let l be limit_ordinal non empty Ordinal; for U being Universe st l in U & ( for a being Ordinal st a in l holds
(U -Veblen) . a is normal Ordinal-Sequence of U ) holds
(U -Veblen) . l is normal Ordinal-Sequence of U
let U be Universe; ( l in U & ( for a being Ordinal st a in l holds
(U -Veblen) . a is normal Ordinal-Sequence of U ) implies (U -Veblen) . l is normal Ordinal-Sequence of U )
assume A1:
l in U
; ( ex a being Ordinal st
( a in l & (U -Veblen) . a is not normal Ordinal-Sequence of U ) or (U -Veblen) . l is normal Ordinal-Sequence of U )
assume A2:
for a being Ordinal st a in l holds
(U -Veblen) . a is normal Ordinal-Sequence of U
; (U -Veblen) . l is normal Ordinal-Sequence of U
A3:
l in On U
by A1, ORDINAL1:def 9;
then A4:
(U -Veblen) . l = criticals ((U -Veblen) | l)
by Def15;
A5:
dom (U -Veblen) = On U
by Def15;
l c= On U
by A3, ORDINAL1:def 2;
then A6:
dom ((U -Veblen) | l) = l
by A5, RELAT_1:62;
A7:
dom ((U -Veblen) . l) = On U
proof
set F =
U -Veblen ;
set G =
(U -Veblen) . l;
A8:
0 in l
by ORDINAL3:8;
reconsider f0 =
(U -Veblen) . 0 as
normal Ordinal-Sequence of
U by A2, ORDINAL3:8;
A9:
dom f0 = On U
by FUNCT_2:def 1;
A10:
f0 = ((U -Veblen) | l) . 0
by FUNCT_1:49, ORDINAL3:8;
then
f0 in rng ((U -Veblen) | l)
by A6, A8, FUNCT_1:def 3;
hence
dom ((U -Veblen) . l) c= On U
by A4, A9, Th49;
XBOOLE_0:def 10 On U c= dom ((U -Veblen) . l)
then reconsider lg =
lims ((U -Veblen) | l) as
Ordinal-Sequence of
U by A1, A6, Th56;
A12:
dom lg = On U
by FUNCT_2:def 1;
rng lg c= rng ((U -Veblen) . l)
then A17:
Union lg c= Union ((U -Veblen) . l)
by ZFMISC_1:77;
On U c= Union lg
proof
let a be
Ordinal;
ORDINAL1:def 5 ( not a in On U or a in Union lg )
assume A18:
a in On U
;
a in Union lg
A19:
a in succ a
by ORDINAL1:6;
set X =
{ ((((U -Veblen) | l) . b) . (succ a)) where b is Element of dom ((U -Veblen) | l) : b in dom ((U -Veblen) | l) } ;
On U is
limit_ordinal
by CLASSES2:51;
then A20:
succ a in On U
by A18, ORDINAL1:28;
then A21:
lg . (succ a) = union { ((((U -Veblen) | l) . b) . (succ a)) where b is Element of dom ((U -Veblen) | l) : b in dom ((U -Veblen) | l) }
by A12, Def12;
A22:
f0 . (succ a) in { ((((U -Veblen) | l) . b) . (succ a)) where b is Element of dom ((U -Veblen) | l) : b in dom ((U -Veblen) | l) }
by A10, A6, A8;
A23:
f0 . a in f0 . (succ a)
by A19, A20, A9, ORDINAL2:def 12;
a c= f0 . a
by A9, A18, ORDINAL4:10;
then
a in f0 . (succ a)
by A23, ORDINAL1:12;
then
a in lg . (succ a)
by A21, A22, TARSKI:def 4;
hence
a in Union lg
by A12, A20, CARD_5:2;
verum
end;
then A24:
On U c= Union ((U -Veblen) . l)
by A17;
A25:
rng ((U -Veblen) . l) c= U
assume
On U c/= dom ((U -Veblen) . l)
;
contradiction
then
dom ((U -Veblen) . l) in On U
by ORDINAL1:16;
then reconsider d =
dom ((U -Veblen) . l) as
Ordinal of
U by ORDINAL1:def 9;
A27:
card d in card U
by CLASSES2:1;
card (rng ((U -Veblen) . l)) c= card d
by CARD_1:12;
then
card (rng ((U -Veblen) . l)) in card U
by A27, ORDINAL1:12;
then reconsider r =
rng ((U -Veblen) . l) as
Element of
U by A25, CLASSES1:1;
union r in U
;
then
Union ((U -Veblen) . l) in On U
by ORDINAL1:def 9;
then
Union ((U -Veblen) . l) in Union ((U -Veblen) . l)
by A24;
hence
contradiction
;
verum
end;
A28:
rng ((U -Veblen) . l) c= On U
then
(U -Veblen) . l is continuous
by A4, A6, Th53;
hence
(U -Veblen) . l is normal Ordinal-Sequence of U
by A4, A7, A28, FUNCT_2:2; verum