Theorem petseq 39711

Description: Generalized partition-equivalence identification.

The partition-side scheme PetParts and the equivalence-side scheme PetErs define the same class of spans (pairs ⟨𝑟, 𝑛⟩).

This plays the same organizational role for lifted spans that mpets 39691 plays for carriers: mpets 39691 identifies MembParts with CoMembErs at the membership-carrier level, while petseq 39711 identifies the corresponding span-level predicates built from Parts and Ers.

Unlike the earlier broad pets 39701, the bridge used here is the type-safe span theorem typesafepets 39710, which restricts to membership block-carriers. Since typedness (𝑟 ∈ Rels and the appropriate carrier condition) is now built directly into PetParts and PetErs, this theorem can be used downstream without repeatedly re-establishing basic typing premises. (Contributed by Peter Mazsa, 19-Feb-2026.)

Assertion

Ref	Expression
petseq	⊢ PetParts = PetErs

Proof of Theorem petseq

Dummy variables 𝑛 𝑟 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		typesafepets 39710	. . . . . . 7 ⊢ ((𝑛 ∈ MembParts ∧ 𝑟 ∈ V) → ((𝑟 ⋉ (◡ E ↾ 𝑛)) Parts 𝑛 ↔ ≀ (𝑟 ⋉ (◡ E ↾ 𝑛)) Ers 𝑛))
2	1	elvd 3459	. . . . . 6 ⊢ (𝑛 ∈ MembParts → ((𝑟 ⋉ (◡ E ↾ 𝑛)) Parts 𝑛 ↔ ≀ (𝑟 ⋉ (◡ E ↾ 𝑛)) Ers 𝑛))
3	2	adantl 487	. . . . 5 ⊢ ((𝑟 ∈ Rels ∧ 𝑛 ∈ MembParts ) → ((𝑟 ⋉ (◡ E ↾ 𝑛)) Parts 𝑛 ↔ ≀ (𝑟 ⋉ (◡ E ↾ 𝑛)) Ers 𝑛))
4	3	pm5.32i 585	. . . 4 ⊢ (((𝑟 ∈ Rels ∧ 𝑛 ∈ MembParts ) ∧ (𝑟 ⋉ (◡ E ↾ 𝑛)) Parts 𝑛) ↔ ((𝑟 ∈ Rels ∧ 𝑛 ∈ MembParts ) ∧ ≀ (𝑟 ⋉ (◡ E ↾ 𝑛)) Ers 𝑛))
5		mpets 39691	. . . . . 6 ⊢ MembParts = CoMembErs
6	5	eleq2i 2854	. . . . 5 ⊢ (𝑛 ∈ MembParts ↔ 𝑛 ∈ CoMembErs )
7	6	anbi2i 635	. . . 4 ⊢ ((𝑟 ∈ Rels ∧ 𝑛 ∈ MembParts ) ↔ (𝑟 ∈ Rels ∧ 𝑛 ∈ CoMembErs ))
8	4, 7	bianbi 639	. . 3 ⊢ (((𝑟 ∈ Rels ∧ 𝑛 ∈ MembParts ) ∧ (𝑟 ⋉ (◡ E ↾ 𝑛)) Parts 𝑛) ↔ ((𝑟 ∈ Rels ∧ 𝑛 ∈ CoMembErs ) ∧ ≀ (𝑟 ⋉ (◡ E ↾ 𝑛)) Ers 𝑛))
9	8	opabbii 5176	. 2 ⊢ {⟨𝑟, 𝑛⟩ ∣ ((𝑟 ∈ Rels ∧ 𝑛 ∈ MembParts ) ∧ (𝑟 ⋉ (◡ E ↾ 𝑛)) Parts 𝑛)} = {⟨𝑟, 𝑛⟩ ∣ ((𝑟 ∈ Rels ∧ 𝑛 ∈ CoMembErs ) ∧ ≀ (𝑟 ⋉ (◡ E ↾ 𝑛)) Ers 𝑛)}
10		df-petparts 39703	. 2 ⊢ PetParts = {⟨𝑟, 𝑛⟩ ∣ ((𝑟 ∈ Rels ∧ 𝑛 ∈ MembParts ) ∧ (𝑟 ⋉ (◡ E ↾ 𝑛)) Parts 𝑛)}
11		df-peters 39704	. 2 ⊢ PetErs = {⟨𝑟, 𝑛⟩ ∣ ((𝑟 ∈ Rels ∧ 𝑛 ∈ CoMembErs ) ∧ ≀ (𝑟 ⋉ (◡ E ↾ 𝑛)) Ers 𝑛)}
12	9, 10, 11	3eqtr4i 2795	1 ⊢ PetParts = PetErs

This proof depends on syntax axioms:   ↔ wb 209   ∧ wa 401   = wceq 1570   ∈ wcel 2145  Vcvv 3453   class class class wbr 5107  {copab 5171   E cep 5558  ^◡ccnv 5658   ↾ cres 5661   ⋉ cxrn 38909   ≀ ccoss 38918   Rels crels 38920   Ers cers 38943   PetErs cpeters 38945   CoMembErs ccomembers 38947   Parts cparts 38958   MembParts cmembparts 38960   PetParts cpetparts 38962

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2215  ax-ext 2734  ax-rep 5236  ax-sep 5255  ax-nul 5267  ax-pow 5334  ax-pr 5402  ax-un 7739

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ne 2958  df-ral 3079  df-rex 3089  df-rmo 3367  df-rab 3415  df-v 3455  df-dif 3905  df-un 3907  df-in 3909  df-ss 3919  df-nul 4283  df-if 4486  df-pw 4562  df-sn 4588  df-pr 4590  df-op 4594  df-uni 4871  df-iun 4956  df-br 5108  df-opab 5172  df-mpt 5191  df-id 5554  df-eprel 5559  df-xp 5665  df-rel 5666  df-cnv 5667  df-co 5668  df-dm 5669  df-rn 5670  df-res 5671  df-ima 5672  df-iota 6493  df-fun 6539  df-fn 6540  df-f 6541  df-fo 6543  df-fv 6545  df-1st 7989  df-2nd 7990  df-ec 8701  df-qs 8705  df-xrn 39115  df-rels 39175  df-coss 39236  df-coels 39237  df-ssr 39313  df-refs 39325  df-refrels 39326  df-refrel 39327  df-cnvrefs 39340  df-cnvrefrels 39341  df-cnvrefrel 39342  df-syms 39357  df-symrels 39358  df-symrel 39359  df-trs 39391  df-trrels 39392  df-trrel 39393  df-eqvrels 39403  df-eqvrel 39404  df-coeleqvrel 39406  df-dmqss 39457  df-dmqs 39458  df-ers 39483  df-erALTV 39484  df-comembers 39485  df-comember 39486  df-funALTV 39502  df-disjss 39523  df-disjs 39524  df-disjALTV 39525  df-eldisj 39527  df-parts 39603  df-part 39604  df-membparts 39605  df-membpart 39606  df-petparts 39703  df-peters 39704

This theorem is used by:  pets2eq  39712