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

Theorem ordsucg 4495
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 4493 . 2  |-  ( Ord 
A  ->  Ord  suc  A
)
2 sucidg 4410 . . 3  |-  ( A  e.  _V  ->  A  e.  suc  A )
3 ordelord 4375 . . . 4  |-  ( ( Ord  suc  A  /\  A  e.  suc  A )  ->  Ord  A )
43ex 115 . . 3  |-  ( Ord 
suc  A  ->  ( A  e.  suc  A  ->  Ord  A ) )
52, 4syl5com 29 . 2  |-  ( A  e.  _V  ->  ( Ord  suc  A  ->  Ord  A ) )
61, 5impbid2 143 1  |-  ( A  e.  _V  ->  ( Ord  A  <->  Ord  suc  A )
)
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 105    e. wcel 2146   _Vcvv 2735   Ord word 4356   suc csuc 4359
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 709  ax-5 1445  ax-7 1446  ax-gen 1447  ax-ie1 1491  ax-ie2 1492  ax-8 1502  ax-10 1503  ax-11 1504  ax-i12 1505  ax-bndl 1507  ax-4 1508  ax-17 1524  ax-i9 1528  ax-ial 1532  ax-i5r 1533  ax-ext 2157
This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-nf 1459  df-sb 1761  df-clab 2162  df-cleq 2168  df-clel 2171  df-nfc 2306  df-ral 2458  df-rex 2459  df-v 2737  df-un 3131  df-in 3133  df-ss 3140  df-sn 3595  df-uni 3806  df-tr 4097  df-iord 4360  df-suc 4365
This theorem is referenced by:  sucelon  4496
  Copyright terms: Public domain W3C validator