Metamath Proof Explorer


Theorem scutbdaybnd2lim

Description: An upper bound on the birthday of a surreal cut when it is a limit birthday. (Contributed by Scott Fenton, 7-Aug-2024)

Ref Expression
Assertion scutbdaybnd2lim
|- ( ( A < ( bday ` ( A |s B ) ) C_ U. ( bday " ( A u. B ) ) )

Proof

Step Hyp Ref Expression
1 scutbdaybnd2
 |-  ( A < ( bday ` ( A |s B ) ) C_ suc U. ( bday " ( A u. B ) ) )
2 1 adantr
 |-  ( ( A < ( bday ` ( A |s B ) ) C_ suc U. ( bday " ( A u. B ) ) )
3 bdayfun
 |-  Fun bday
4 ssltex1
 |-  ( A < A e. _V )
5 ssltex2
 |-  ( A < B e. _V )
6 unexg
 |-  ( ( A e. _V /\ B e. _V ) -> ( A u. B ) e. _V )
7 4 5 6 syl2anc
 |-  ( A < ( A u. B ) e. _V )
8 funimaexg
 |-  ( ( Fun bday /\ ( A u. B ) e. _V ) -> ( bday " ( A u. B ) ) e. _V )
9 3 7 8 sylancr
 |-  ( A < ( bday " ( A u. B ) ) e. _V )
10 9 uniexd
 |-  ( A < U. ( bday " ( A u. B ) ) e. _V )
11 10 adantr
 |-  ( ( A < U. ( bday " ( A u. B ) ) e. _V )
12 nlimsucg
 |-  ( U. ( bday " ( A u. B ) ) e. _V -> -. Lim suc U. ( bday " ( A u. B ) ) )
13 11 12 syl
 |-  ( ( A < -. Lim suc U. ( bday " ( A u. B ) ) )
14 limeq
 |-  ( ( bday ` ( A |s B ) ) = suc U. ( bday " ( A u. B ) ) -> ( Lim ( bday ` ( A |s B ) ) <-> Lim suc U. ( bday " ( A u. B ) ) ) )
15 14 biimpcd
 |-  ( Lim ( bday ` ( A |s B ) ) -> ( ( bday ` ( A |s B ) ) = suc U. ( bday " ( A u. B ) ) -> Lim suc U. ( bday " ( A u. B ) ) ) )
16 15 adantl
 |-  ( ( A < ( ( bday ` ( A |s B ) ) = suc U. ( bday " ( A u. B ) ) -> Lim suc U. ( bday " ( A u. B ) ) ) )
17 13 16 mtod
 |-  ( ( A < -. ( bday ` ( A |s B ) ) = suc U. ( bday " ( A u. B ) ) )
18 17 neqned
 |-  ( ( A < ( bday ` ( A |s B ) ) =/= suc U. ( bday " ( A u. B ) ) )
19 bdayelon
 |-  ( bday ` ( A |s B ) ) e. On
20 19 onordi
 |-  Ord ( bday ` ( A |s B ) )
21 imassrn
 |-  ( bday " ( A u. B ) ) C_ ran bday
22 bdayrn
 |-  ran bday = On
23 21 22 sseqtri
 |-  ( bday " ( A u. B ) ) C_ On
24 ssorduni
 |-  ( ( bday " ( A u. B ) ) C_ On -> Ord U. ( bday " ( A u. B ) ) )
25 23 24 ax-mp
 |-  Ord U. ( bday " ( A u. B ) )
26 ordsuc
 |-  ( Ord U. ( bday " ( A u. B ) ) <-> Ord suc U. ( bday " ( A u. B ) ) )
27 25 26 mpbi
 |-  Ord suc U. ( bday " ( A u. B ) )
28 ordelssne
 |-  ( ( Ord ( bday ` ( A |s B ) ) /\ Ord suc U. ( bday " ( A u. B ) ) ) -> ( ( bday ` ( A |s B ) ) e. suc U. ( bday " ( A u. B ) ) <-> ( ( bday ` ( A |s B ) ) C_ suc U. ( bday " ( A u. B ) ) /\ ( bday ` ( A |s B ) ) =/= suc U. ( bday " ( A u. B ) ) ) ) )
29 20 27 28 mp2an
 |-  ( ( bday ` ( A |s B ) ) e. suc U. ( bday " ( A u. B ) ) <-> ( ( bday ` ( A |s B ) ) C_ suc U. ( bday " ( A u. B ) ) /\ ( bday ` ( A |s B ) ) =/= suc U. ( bday " ( A u. B ) ) ) )
30 2 18 29 sylanbrc
 |-  ( ( A < ( bday ` ( A |s B ) ) e. suc U. ( bday " ( A u. B ) ) )
31 19 a1i
 |-  ( ( A < ( bday ` ( A |s B ) ) e. On )
32 ordsssuc
 |-  ( ( ( bday ` ( A |s B ) ) e. On /\ Ord U. ( bday " ( A u. B ) ) ) -> ( ( bday ` ( A |s B ) ) C_ U. ( bday " ( A u. B ) ) <-> ( bday ` ( A |s B ) ) e. suc U. ( bday " ( A u. B ) ) ) )
33 31 25 32 sylancl
 |-  ( ( A < ( ( bday ` ( A |s B ) ) C_ U. ( bday " ( A u. B ) ) <-> ( bday ` ( A |s B ) ) e. suc U. ( bday " ( A u. B ) ) ) )
34 30 33 mpbird
 |-  ( ( A < ( bday ` ( A |s B ) ) C_ U. ( bday " ( A u. B ) ) )