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Theorem zeneo 12382
Description: No even integer equals an odd integer (i.e. no integer can be both even and odd). Exercise 10(a) of [Apostol] p. 28. This variant of zneo 9548 follows immediately from the fact that a contradiction implies anything, see pm2.21i 649. (Contributed by AV, 22-Jun-2021.)
Assertion
Ref Expression
zeneo  |-  ( ( A  e.  ZZ  /\  B  e.  ZZ )  ->  ( ( 2  ||  A  /\  -.  2  ||  B )  ->  A  =/=  B ) )

Proof of Theorem zeneo
StepHypRef Expression
1 nbrne1 4102 . 2  |-  ( ( 2  ||  A  /\  -.  2  ||  B )  ->  A  =/=  B
)
21a1i 9 1  |-  ( ( A  e.  ZZ  /\  B  e.  ZZ )  ->  ( ( 2  ||  A  /\  -.  2  ||  B )  ->  A  =/=  B ) )
Colors of variables: wff set class
Syntax hints:   -. wn 3    -> wi 4    /\ wa 104    e. wcel 2200    =/= wne 2400   class class class wbr 4083   2c2 9161   ZZcz 9446    || cdvds 12298
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 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-ext 2211
This theorem depends on definitions:  df-bi 117  df-3an 1004  df-tru 1398  df-nf 1507  df-sb 1809  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ne 2401  df-v 2801  df-un 3201  df-sn 3672  df-pr 3673  df-op 3675  df-br 4084
This theorem is referenced by: (None)
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