ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  ordsucg Unicode version

Theorem ordsucg 4413
Description: The successor of an ordinal class is ordinal. (Contributed by Jim Kingdon, 20-Nov-2018.)
Assertion
Ref Expression
ordsucg  |-  ( A  e.  _V  ->  ( Ord  A  <->  Ord  suc  A )
)

Proof of Theorem ordsucg
StepHypRef Expression
1 ordsucim 4411 . 2  |-  ( Ord 
A  ->  Ord  suc  A
)
2 sucidg 4333 . . 3  |-  ( A  e.  _V  ->  A  e.  suc  A )
3 ordelord 4298 . . . 4  |-  ( ( Ord  suc  A  /\  A  e.  suc  A )  ->  Ord  A )
43ex 114 . . 3  |-  ( Ord 
suc  A  ->  ( A  e.  suc  A  ->  Ord  A ) )
52, 4syl5com 29 . 2  |-  ( A  e.  _V  ->  ( Ord  suc  A  ->  Ord  A ) )
61, 5impbid2 142 1  |-  ( A  e.  _V  ->  ( Ord  A  <->  Ord  suc  A )
)
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 104    e. wcel 1480   _Vcvv 2681   Ord word 4279   suc csuc 4282
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 698  ax-5 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-10 1483  ax-11 1484  ax-i12 1485  ax-bndl 1486  ax-4 1487  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2119
This theorem depends on definitions:  df-bi 116  df-3an 964  df-tru 1334  df-nf 1437  df-sb 1736  df-clab 2124  df-cleq 2130  df-clel 2133  df-nfc 2268  df-ral 2419  df-rex 2420  df-v 2683  df-un 3070  df-in 3072  df-ss 3079  df-sn 3528  df-uni 3732  df-tr 4022  df-iord 4283  df-suc 4288
This theorem is referenced by:  sucelon  4414
  Copyright terms: Public domain W3C validator