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Theorem iseven 47790
Description: The predicate "is an even number". An even number is an integer which is divisible by 2, i.e. the result of dividing the even integer by 2 is still an integer. (Contributed by AV, 14-Jun-2020.)
Assertion
Ref Expression
iseven (𝑍 ∈ Even ↔ (𝑍 ∈ ℤ ∧ (𝑍 / 2) ∈ ℤ))

Proof of Theorem iseven
Dummy variable 𝑧 is distinct from all other variables.
StepHypRef Expression
1 oveq1 7362 . . 3 (𝑧 = 𝑍 → (𝑧 / 2) = (𝑍 / 2))
21eleq1d 2818 . 2 (𝑧 = 𝑍 → ((𝑧 / 2) ∈ ℤ ↔ (𝑍 / 2) ∈ ℤ))
3 df-even 47788 . 2 Even = {𝑧 ∈ ℤ ∣ (𝑧 / 2) ∈ ℤ}
42, 3elrab2 3646 1 (𝑍 ∈ Even ↔ (𝑍 ∈ ℤ ∧ (𝑍 / 2) ∈ ℤ))
Colors of variables: wff setvar class
Syntax hints:  wb 206  wa 395   = wceq 1541  wcel 2113  (class class class)co 7355   / cdiv 11785  2c2 12191  cz 12479   Even ceven 47786
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1968  ax-7 2009  ax-8 2115  ax-9 2123  ax-ext 2705
This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-3an 1088  df-tru 1544  df-fal 1554  df-ex 1781  df-sb 2068  df-clab 2712  df-cleq 2725  df-clel 2808  df-rab 3397  df-v 3439  df-dif 3901  df-un 3903  df-ss 3915  df-nul 4283  df-if 4477  df-sn 4578  df-pr 4580  df-op 4584  df-uni 4861  df-br 5096  df-iota 6445  df-fv 6497  df-ov 7358  df-even 47788
This theorem is referenced by:  evenz  47792  evendiv2z  47794  evenm1odd  47801  evenp1odd  47802  oddp1eveni  47803  oddm1eveni  47804  evennodd  47805  oddneven  47806  enege  47807  zeoALTV  47832  oddm1evenALTV  47837  oddp1evenALTV  47838  0evenALTV  47850  2evenALTV  47854  6even  47873  8even  47875
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