Metamath Proof Explorer


Theorem nolesgn2ores

Description: Given A less than or equal to B , equal to B up to X , and A ( X ) = 2o , then ` ( A |`` suc X ) = ( B |`suc X ) . (Contributed by Scott Fenton, 6-Dec-2021)

Ref Expression
Assertion nolesgn2ores
|- ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( A |` suc X ) = ( B |` suc X ) )

Proof

Step Hyp Ref Expression
1 dmres
 |-  dom ( A |` suc X ) = ( suc X i^i dom A )
2 simp11
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  A e. No )
3 nodmord
 |-  ( A e. No -> Ord dom A )
4 2 3 syl
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  Ord dom A )
5 ndmfv
 |-  ( -. X e. dom A -> ( A ` X ) = (/) )
6 2on
 |-  2o e. On
7 6 elexi
 |-  2o e. _V
8 7 prid2
 |-  2o e. { 1o , 2o }
9 8 nosgnn0i
 |-  (/) =/= 2o
10 neeq1
 |-  ( ( A ` X ) = (/) -> ( ( A ` X ) =/= 2o <-> (/) =/= 2o ) )
11 9 10 mpbiri
 |-  ( ( A ` X ) = (/) -> ( A ` X ) =/= 2o )
12 11 neneqd
 |-  ( ( A ` X ) = (/) -> -. ( A ` X ) = 2o )
13 5 12 syl
 |-  ( -. X e. dom A -> -. ( A ` X ) = 2o )
14 13 con4i
 |-  ( ( A ` X ) = 2o -> X e. dom A )
15 14 adantl
 |-  ( ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) -> X e. dom A )
16 15 3ad2ant2
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  X e. dom A )
17 ordsucss
 |-  ( Ord dom A -> ( X e. dom A -> suc X C_ dom A ) )
18 4 16 17 sylc
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  suc X C_ dom A )
19 df-ss
 |-  ( suc X C_ dom A <-> ( suc X i^i dom A ) = suc X )
20 18 19 sylib
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( suc X i^i dom A ) = suc X )
21 1 20 syl5eq
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  dom ( A |` suc X ) = suc X )
22 dmres
 |-  dom ( B |` suc X ) = ( suc X i^i dom B )
23 simp12
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  B e. No )
24 nodmord
 |-  ( B e. No -> Ord dom B )
25 23 24 syl
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  Ord dom B )
26 nolesgn2o
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( B ` X ) = 2o )
27 ndmfv
 |-  ( -. X e. dom B -> ( B ` X ) = (/) )
28 neeq1
 |-  ( ( B ` X ) = (/) -> ( ( B ` X ) =/= 2o <-> (/) =/= 2o ) )
29 9 28 mpbiri
 |-  ( ( B ` X ) = (/) -> ( B ` X ) =/= 2o )
30 29 neneqd
 |-  ( ( B ` X ) = (/) -> -. ( B ` X ) = 2o )
31 27 30 syl
 |-  ( -. X e. dom B -> -. ( B ` X ) = 2o )
32 31 con4i
 |-  ( ( B ` X ) = 2o -> X e. dom B )
33 26 32 syl
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  X e. dom B )
34 ordsucss
 |-  ( Ord dom B -> ( X e. dom B -> suc X C_ dom B ) )
35 25 33 34 sylc
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  suc X C_ dom B )
36 df-ss
 |-  ( suc X C_ dom B <-> ( suc X i^i dom B ) = suc X )
37 35 36 sylib
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( suc X i^i dom B ) = suc X )
38 22 37 syl5eq
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  dom ( B |` suc X ) = suc X )
39 21 38 eqtr4d
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  dom ( A |` suc X ) = dom ( B |` suc X ) )
40 21 eleq2d
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( x e. dom ( A |` suc X ) <-> x e. suc X ) )
41 vex
 |-  x e. _V
42 41 elsuc
 |-  ( x e. suc X <-> ( x e. X \/ x = X ) )
43 simp2l
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( A |` X ) = ( B |` X ) )
44 43 fveq1d
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( ( A |` X ) ` x ) = ( ( B |` X ) ` x ) )
45 44 adantr
 |-  ( ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( ( A |` X ) ` x ) = ( ( B |` X ) ` x ) )
46 simpr
 |-  ( ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  x e. X )
47 46 fvresd
 |-  ( ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( ( A |` X ) ` x ) = ( A ` x ) )
48 46 fvresd
 |-  ( ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( ( B |` X ) ` x ) = ( B ` x ) )
49 45 47 48 3eqtr3d
 |-  ( ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( A ` x ) = ( B ` x ) )
50 49 ex
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( x e. X -> ( A ` x ) = ( B ` x ) ) )
51 simp2r
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( A ` X ) = 2o )
52 51 26 eqtr4d
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( A ` X ) = ( B ` X ) )
53 fveq2
 |-  ( x = X -> ( A ` x ) = ( A ` X ) )
54 fveq2
 |-  ( x = X -> ( B ` x ) = ( B ` X ) )
55 53 54 eqeq12d
 |-  ( x = X -> ( ( A ` x ) = ( B ` x ) <-> ( A ` X ) = ( B ` X ) ) )
56 52 55 syl5ibrcom
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( x = X -> ( A ` x ) = ( B ` x ) ) )
57 50 56 jaod
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( ( x e. X \/ x = X ) -> ( A ` x ) = ( B ` x ) ) )
58 42 57 syl5bi
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( x e. suc X -> ( A ` x ) = ( B ` x ) ) )
59 58 imp
 |-  ( ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( A ` x ) = ( B ` x ) )
60 simpr
 |-  ( ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  x e. suc X )
61 60 fvresd
 |-  ( ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( ( A |` suc X ) ` x ) = ( A ` x ) )
62 60 fvresd
 |-  ( ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( ( B |` suc X ) ` x ) = ( B ` x ) )
63 59 61 62 3eqtr4d
 |-  ( ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( ( A |` suc X ) ` x ) = ( ( B |` suc X ) ` x ) )
64 63 ex
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( x e. suc X -> ( ( A |` suc X ) ` x ) = ( ( B |` suc X ) ` x ) ) )
65 40 64 sylbid
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( x e. dom ( A |` suc X ) -> ( ( A |` suc X ) ` x ) = ( ( B |` suc X ) ` x ) ) )
66 65 ralrimiv
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  A. x e. dom ( A |` suc X ) ( ( A |` suc X ) ` x ) = ( ( B |` suc X ) ` x ) )
67 nofun
 |-  ( A e. No -> Fun A )
68 funres
 |-  ( Fun A -> Fun ( A |` suc X ) )
69 2 67 68 3syl
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  Fun ( A |` suc X ) )
70 nofun
 |-  ( B e. No -> Fun B )
71 funres
 |-  ( Fun B -> Fun ( B |` suc X ) )
72 23 70 71 3syl
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  Fun ( B |` suc X ) )
73 eqfunfv
 |-  ( ( Fun ( A |` suc X ) /\ Fun ( B |` suc X ) ) -> ( ( A |` suc X ) = ( B |` suc X ) <-> ( dom ( A |` suc X ) = dom ( B |` suc X ) /\ A. x e. dom ( A |` suc X ) ( ( A |` suc X ) ` x ) = ( ( B |` suc X ) ` x ) ) ) )
74 69 72 73 syl2anc
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( ( A |` suc X ) = ( B |` suc X ) <-> ( dom ( A |` suc X ) = dom ( B |` suc X ) /\ A. x e. dom ( A |` suc X ) ( ( A |` suc X ) ` x ) = ( ( B |` suc X ) ` x ) ) ) )
75 39 66 74 mpbir2and
 |-  ( ( ( A e. No /\ B e. No /\ X e. On ) /\ ( ( A |` X ) = ( B |` X ) /\ ( A ` X ) = 2o ) /\ -. B  ( A |` suc X ) = ( B |` suc X ) )