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Theorem ispcmp 32825
Description: The predicate "is a paracompact topology". (Contributed by Thierry Arnoux, 7-Jan-2020.)
Assertion
Ref Expression
ispcmp (𝐽 ∈ Paracomp ↔ 𝐽 ∈ CovHasRef(LocFinβ€˜π½))

Proof of Theorem ispcmp
Dummy variable 𝑗 is distinct from all other variables.
StepHypRef Expression
1 elex 3492 . 2 (𝐽 ∈ Paracomp β†’ 𝐽 ∈ V)
2 elex 3492 . 2 (𝐽 ∈ CovHasRef(LocFinβ€˜π½) β†’ 𝐽 ∈ V)
3 id 22 . . . 4 (𝑗 = 𝐽 β†’ 𝑗 = 𝐽)
4 fveq2 6888 . . . . 5 (𝑗 = 𝐽 β†’ (LocFinβ€˜π‘—) = (LocFinβ€˜π½))
5 crefeq 32813 . . . . 5 ((LocFinβ€˜π‘—) = (LocFinβ€˜π½) β†’ CovHasRef(LocFinβ€˜π‘—) = CovHasRef(LocFinβ€˜π½))
64, 5syl 17 . . . 4 (𝑗 = 𝐽 β†’ CovHasRef(LocFinβ€˜π‘—) = CovHasRef(LocFinβ€˜π½))
73, 6eleq12d 2827 . . 3 (𝑗 = 𝐽 β†’ (𝑗 ∈ CovHasRef(LocFinβ€˜π‘—) ↔ 𝐽 ∈ CovHasRef(LocFinβ€˜π½)))
8 df-pcmp 32824 . . 3 Paracomp = {𝑗 ∣ 𝑗 ∈ CovHasRef(LocFinβ€˜π‘—)}
97, 8elab2g 3669 . 2 (𝐽 ∈ V β†’ (𝐽 ∈ Paracomp ↔ 𝐽 ∈ CovHasRef(LocFinβ€˜π½)))
101, 2, 9pm5.21nii 379 1 (𝐽 ∈ Paracomp ↔ 𝐽 ∈ CovHasRef(LocFinβ€˜π½))
Colors of variables: wff setvar class
Syntax hints:   ↔ wb 205   = wceq 1541   ∈ wcel 2106  Vcvv 3474  β€˜cfv 6540  LocFinclocfin 22999  CovHasRefccref 32810  Paracompcpcmp 32823
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1913  ax-6 1971  ax-7 2011  ax-8 2108  ax-9 2116  ax-ext 2703
This theorem depends on definitions:  df-bi 206  df-an 397  df-or 846  df-3an 1089  df-tru 1544  df-fal 1554  df-ex 1782  df-sb 2068  df-clab 2710  df-cleq 2724  df-clel 2810  df-ral 3062  df-rex 3071  df-rab 3433  df-v 3476  df-dif 3950  df-un 3952  df-in 3954  df-ss 3964  df-nul 4322  df-if 4528  df-sn 4628  df-pr 4630  df-op 4634  df-uni 4908  df-br 5148  df-iota 6492  df-fv 6548  df-cref 32811  df-pcmp 32824
This theorem is referenced by:  cmppcmp  32826  dispcmp  32827  pcmplfin  32828
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