let l be limit_ordinal non empty Ordinal; for U being Universe st l in U & ( for a being ordinal number 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 number 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 Z0:
l in U
; ( ex a being ordinal number 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 Z1:
for a being ordinal number st a in l holds
(U -Veblen) . a is normal Ordinal-Sequence of U
; (U -Veblen) . l is normal Ordinal-Sequence of U
A0:
l in On U
by Z0, ORDINAL1:def 9;
then A1:
(U -Veblen) . l = criticals ((U -Veblen) | l)
by V;
A3:
dom (U -Veblen) = On U
by V;
l c= On U
by A0, ORDINAL1:def 2;
then A2:
dom ((U -Veblen) | l) = l
by A3, RELAT_1:62;
YY:
dom ((U -Veblen) . l) = On U
proof
set F =
U -Veblen ;
set G =
(U -Veblen) . l;
H1:
0 in l
by ORDINAL3:8;
reconsider f0 =
(U -Veblen) . 0 as
normal Ordinal-Sequence of
U by Z1, ORDINAL3:8;
H2:
dom f0 = On U
by FUNCT_2:def 1;
H2a:
f0 = ((U -Veblen) | l) . 0
by FUNCT_1:49, ORDINAL3:8;
then
f0 in rng ((U -Veblen) | l)
by A2, H1, FUNCT_1:def 3;
hence
dom ((U -Veblen) . l) c= On U
by A1, H2, ThA5;
XBOOLE_0:def 10 On U c= dom ((U -Veblen) . l)
then reconsider lg =
lims ((U -Veblen) | l) as
Ordinal-Sequence of
U by Z0, A2, ThL1;
H3:
dom lg = On U
by FUNCT_2:def 1;
rng lg c= rng ((U -Veblen) . l)
then F1:
Union lg c= Union ((U -Veblen) . l)
by ZFMISC_1:77;
On U c= Union lg
proof
let a be
ordinal number ;
ORDINAL1:def 5 ( not a in On U or a in Union lg )
assume E1:
a in On U
;
a in Union lg
E2:
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 E3:
succ a in On U
by E1, ORDINAL1:28;
then E4:
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 H3, LIM;
E5:
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 H2a, A2, H1;
E6:
f0 . a in f0 . (succ a)
by E2, E3, H2, ORDINAL2:def 12;
a c= f0 . a
by H2, E1, ORDINAL4:10;
then
a in f0 . (succ a)
by E6, ORDINAL1:12;
then
a in lg . (succ a)
by E4, E5, TARSKI:def 4;
hence
a in Union lg
by H3, E3, CARD_5:2;
verum
end;
then F2:
On U c= Union ((U -Veblen) . l)
by F1, XBOOLE_1:1;
F3:
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;
H5:
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 H5, ORDINAL1:12;
then reconsider r =
rng ((U -Veblen) . l) as
Element of
U by F3, 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 F2;
hence
contradiction
;
verum
end;
ZZ:
rng ((U -Veblen) . l) c= On U
then
(U -Veblen) . l is continuous
by A1, A2, ThAA;
hence
(U -Veblen) . l is normal Ordinal-Sequence of U
by A1, YY, ZZ, FUNCT_2:2; verum