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Theorem phplem3g 6978
Description: A natural number is equinumerous to its successor minus any element of the successor. Version of phplem3 6976 with unnecessary hypotheses removed. (Contributed by Jim Kingdon, 1-Sep-2021.)
Assertion
Ref Expression
phplem3g  |-  ( ( A  e.  om  /\  B  e.  suc  A )  ->  A  ~~  ( suc  A  \  { B } ) )

Proof of Theorem phplem3g
Dummy variables  a  b are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 eleq1 2270 . . . . 5  |-  ( b  =  B  ->  (
b  e.  suc  A  <->  B  e.  suc  A ) )
21anbi2d 464 . . . 4  |-  ( b  =  B  ->  (
( A  e.  om  /\  b  e.  suc  A
)  <->  ( A  e. 
om  /\  B  e.  suc  A ) ) )
3 sneq 3654 . . . . . 6  |-  ( b  =  B  ->  { b }  =  { B } )
43difeq2d 3299 . . . . 5  |-  ( b  =  B  ->  ( suc  A  \  { b } )  =  ( suc  A  \  { B } ) )
54breq2d 4071 . . . 4  |-  ( b  =  B  ->  ( A  ~~  ( suc  A  \  { b } )  <-> 
A  ~~  ( suc  A 
\  { B }
) ) )
62, 5imbi12d 234 . . 3  |-  ( b  =  B  ->  (
( ( A  e. 
om  /\  b  e.  suc  A )  ->  A  ~~  ( suc  A  \  { b } ) )  <->  ( ( A  e.  om  /\  B  e.  suc  A )  ->  A  ~~  ( suc  A  \  { B } ) ) ) )
7 eleq1 2270 . . . . . . 7  |-  ( a  =  A  ->  (
a  e.  om  <->  A  e.  om ) )
8 suceq 4467 . . . . . . . 8  |-  ( a  =  A  ->  suc  a  =  suc  A )
98eleq2d 2277 . . . . . . 7  |-  ( a  =  A  ->  (
b  e.  suc  a  <->  b  e.  suc  A ) )
107, 9anbi12d 473 . . . . . 6  |-  ( a  =  A  ->  (
( a  e.  om  /\  b  e.  suc  a
)  <->  ( A  e. 
om  /\  b  e.  suc  A ) ) )
11 id 19 . . . . . . 7  |-  ( a  =  A  ->  a  =  A )
128difeq1d 3298 . . . . . . 7  |-  ( a  =  A  ->  ( suc  a  \  { b } )  =  ( suc  A  \  {
b } ) )
1311, 12breq12d 4072 . . . . . 6  |-  ( a  =  A  ->  (
a  ~~  ( suc  a  \  { b } )  <->  A  ~~  ( suc 
A  \  { b } ) ) )
1410, 13imbi12d 234 . . . . 5  |-  ( a  =  A  ->  (
( ( a  e. 
om  /\  b  e.  suc  a )  ->  a  ~~  ( suc  a  \  { b } ) )  <->  ( ( A  e.  om  /\  b  e.  suc  A )  ->  A  ~~  ( suc  A  \  { b } ) ) ) )
15 vex 2779 . . . . . 6  |-  a  e. 
_V
16 vex 2779 . . . . . 6  |-  b  e. 
_V
1715, 16phplem3 6976 . . . . 5  |-  ( ( a  e.  om  /\  b  e.  suc  a )  ->  a  ~~  ( suc  a  \  { b } ) )
1814, 17vtoclg 2838 . . . 4  |-  ( A  e.  om  ->  (
( A  e.  om  /\  b  e.  suc  A
)  ->  A  ~~  ( suc  A  \  {
b } ) ) )
1918anabsi5 579 . . 3  |-  ( ( A  e.  om  /\  b  e.  suc  A )  ->  A  ~~  ( suc  A  \  { b } ) )
206, 19vtoclg 2838 . 2  |-  ( B  e.  suc  A  -> 
( ( A  e. 
om  /\  B  e.  suc  A )  ->  A  ~~  ( suc  A  \  { B } ) ) )
2120anabsi7 581 1  |-  ( ( A  e.  om  /\  B  e.  suc  A )  ->  A  ~~  ( suc  A  \  { B } ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104    = wceq 1373    e. wcel 2178    \ cdif 3171   {csn 3643   class class class wbr 4059   suc csuc 4430   omcom 4656    ~~ cen 6848
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-in1 615  ax-in2 616  ax-io 711  ax-5 1471  ax-7 1472  ax-gen 1473  ax-ie1 1517  ax-ie2 1518  ax-8 1528  ax-10 1529  ax-11 1530  ax-i12 1531  ax-bndl 1533  ax-4 1534  ax-17 1550  ax-i9 1554  ax-ial 1558  ax-i5r 1559  ax-13 2180  ax-14 2181  ax-ext 2189  ax-sep 4178  ax-nul 4186  ax-pow 4234  ax-pr 4269  ax-un 4498  ax-setind 4603  ax-iinf 4654
This theorem depends on definitions:  df-bi 117  df-dc 837  df-3or 982  df-3an 983  df-tru 1376  df-fal 1379  df-nf 1485  df-sb 1787  df-eu 2058  df-mo 2059  df-clab 2194  df-cleq 2200  df-clel 2203  df-nfc 2339  df-ne 2379  df-ral 2491  df-rex 2492  df-rab 2495  df-v 2778  df-dif 3176  df-un 3178  df-in 3180  df-ss 3187  df-nul 3469  df-pw 3628  df-sn 3649  df-pr 3650  df-op 3652  df-uni 3865  df-int 3900  df-br 4060  df-opab 4122  df-tr 4159  df-id 4358  df-iord 4431  df-on 4433  df-suc 4436  df-iom 4657  df-xp 4699  df-rel 4700  df-cnv 4701  df-co 4702  df-dm 4703  df-rn 4704  df-res 4705  df-ima 4706  df-fun 5292  df-fn 5293  df-f 5294  df-f1 5295  df-fo 5296  df-f1o 5297  df-en 6851
This theorem is referenced by:  phplem4dom  6984  phpm  6988  phplem4on  6990
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