Users' Mathboxes Mathbox for Zhi Wang < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >   Mathboxes  >  prcofdiag1 Structured version   Visualization version   GIF version

Theorem prcofdiag1 50322
Description: A constant functor pre-composed by a functor is another constant functor. (Contributed by Zhi Wang, 25-Nov-2025.)
Hypotheses
Ref Expression
prcofdiag.l 𝐿 = (𝐶Δfunc𝐷)
prcofdiag.m 𝑀 = (𝐶Δfunc𝐸)
prcofdiag.f (𝜑𝐹 ∈ (𝐸 Func 𝐷))
prcofdiag.c (𝜑𝐶 ∈ Cat)
prcofdiag1.b 𝐵 = (Base‘𝐶)
prcofdiag1.x (𝜑𝑋𝐵)
Assertion
Ref Expression
prcofdiag1 (𝜑 → (((1st𝐿)‘𝑋) ∘func 𝐹) = ((1st𝑀)‘𝑋))

Proof of Theorem prcofdiag1
Dummy variables 𝑓 𝑥 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 eqid 2760 . . . . . 6 (Base‘𝐸) = (Base‘𝐸)
2 prcofdiag1.b . . . . . 6 𝐵 = (Base‘𝐶)
3 prcofdiag.f . . . . . . . 8 (𝜑𝐹 ∈ (𝐸 Func 𝐷))
4 prcofdiag.l . . . . . . . . 9 𝐿 = (𝐶Δfunc𝐷)
5 prcofdiag.c . . . . . . . . 9 (𝜑𝐶 ∈ Cat)
63func1st2nd 50005 . . . . . . . . . 10 (𝜑 → (1st𝐹)(𝐸 Func 𝐷)(2nd𝐹))
76funcrcl3 50009 . . . . . . . . 9 (𝜑𝐷 ∈ Cat)
8 prcofdiag1.x . . . . . . . . 9 (𝜑𝑋𝐵)
9 eqid 2760 . . . . . . . . 9 ((1st𝐿)‘𝑋) = ((1st𝐿)‘𝑋)
104, 5, 7, 2, 8, 9diag1cl 18333 . . . . . . . 8 (𝜑 → ((1st𝐿)‘𝑋) ∈ (𝐷 Func 𝐶))
113, 10cofucl 17980 . . . . . . 7 (𝜑 → (((1st𝐿)‘𝑋) ∘func 𝐹) ∈ (𝐸 Func 𝐶))
1211func1st2nd 50005 . . . . . 6 (𝜑 → (1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹))(𝐸 Func 𝐶)(2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹)))
131, 2, 12funcf1 17958 . . . . 5 (𝜑 → (1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹)):(Base‘𝐸)⟶𝐵)
1413ffnd 6704 . . . 4 (𝜑 → (1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹)) Fn (Base‘𝐸))
15 prcofdiag.m . . . . . . . 8 𝑀 = (𝐶Δfunc𝐸)
166funcrcl2 50008 . . . . . . . 8 (𝜑𝐸 ∈ Cat)
17 eqid 2760 . . . . . . . 8 ((1st𝑀)‘𝑋) = ((1st𝑀)‘𝑋)
1815, 5, 16, 2, 8, 17diag1cl 18333 . . . . . . 7 (𝜑 → ((1st𝑀)‘𝑋) ∈ (𝐸 Func 𝐶))
1918func1st2nd 50005 . . . . . 6 (𝜑 → (1st ‘((1st𝑀)‘𝑋))(𝐸 Func 𝐶)(2nd ‘((1st𝑀)‘𝑋)))
201, 2, 19funcf1 17958 . . . . 5 (𝜑 → (1st ‘((1st𝑀)‘𝑋)):(Base‘𝐸)⟶𝐵)
2120ffnd 6704 . . . 4 (𝜑 → (1st ‘((1st𝑀)‘𝑋)) Fn (Base‘𝐸))
225adantr 486 . . . . . 6 ((𝜑𝑥 ∈ (Base‘𝐸)) → 𝐶 ∈ Cat)
237adantr 486 . . . . . 6 ((𝜑𝑥 ∈ (Base‘𝐸)) → 𝐷 ∈ Cat)
248adantr 486 . . . . . 6 ((𝜑𝑥 ∈ (Base‘𝐸)) → 𝑋𝐵)
25 eqid 2760 . . . . . 6 (Base‘𝐷) = (Base‘𝐷)
261, 25, 6funcf1 17958 . . . . . . 7 (𝜑 → (1st𝐹):(Base‘𝐸)⟶(Base‘𝐷))
2726ffvelcdmda 7078 . . . . . 6 ((𝜑𝑥 ∈ (Base‘𝐸)) → ((1st𝐹)‘𝑥) ∈ (Base‘𝐷))
284, 22, 23, 2, 24, 9, 25, 27diag11 18334 . . . . 5 ((𝜑𝑥 ∈ (Base‘𝐸)) → ((1st ‘((1st𝐿)‘𝑋))‘((1st𝐹)‘𝑥)) = 𝑋)
293adantr 486 . . . . . 6 ((𝜑𝑥 ∈ (Base‘𝐸)) → 𝐹 ∈ (𝐸 Func 𝐷))
3010adantr 486 . . . . . 6 ((𝜑𝑥 ∈ (Base‘𝐸)) → ((1st𝐿)‘𝑋) ∈ (𝐷 Func 𝐶))
31 simpr 490 . . . . . 6 ((𝜑𝑥 ∈ (Base‘𝐸)) → 𝑥 ∈ (Base‘𝐸))
321, 29, 30, 31cofu1 17976 . . . . 5 ((𝜑𝑥 ∈ (Base‘𝐸)) → ((1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹))‘𝑥) = ((1st ‘((1st𝐿)‘𝑋))‘((1st𝐹)‘𝑥)))
3316adantr 486 . . . . . 6 ((𝜑𝑥 ∈ (Base‘𝐸)) → 𝐸 ∈ Cat)
3415, 22, 33, 2, 24, 17, 1, 31diag11 18334 . . . . 5 ((𝜑𝑥 ∈ (Base‘𝐸)) → ((1st ‘((1st𝑀)‘𝑋))‘𝑥) = 𝑋)
3528, 32, 343eqtr4d 2805 . . . 4 ((𝜑𝑥 ∈ (Base‘𝐸)) → ((1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹))‘𝑥) = ((1st ‘((1st𝑀)‘𝑋))‘𝑥))
3614, 21, 35eqfnfvd 7026 . . 3 (𝜑 → (1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹)) = (1st ‘((1st𝑀)‘𝑋)))
371, 12funcfn2 17961 . . . 4 (𝜑 → (2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹)) Fn ((Base‘𝐸) × (Base‘𝐸)))
381, 19funcfn2 17961 . . . 4 (𝜑 → (2nd ‘((1st𝑀)‘𝑋)) Fn ((Base‘𝐸) × (Base‘𝐸)))
39 eqid 2760 . . . . . . 7 (Hom ‘𝐸) = (Hom ‘𝐸)
40 eqid 2760 . . . . . . 7 (Hom ‘𝐶) = (Hom ‘𝐶)
4112adantr 486 . . . . . . 7 ((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) → (1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹))(𝐸 Func 𝐶)(2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹)))
42 simprl 783 . . . . . . 7 ((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) → 𝑥 ∈ (Base‘𝐸))
43 simprr 785 . . . . . . 7 ((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) → 𝑦 ∈ (Base‘𝐸))
441, 39, 40, 41, 42, 43funcf2 17960 . . . . . 6 ((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) → (𝑥(2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹))𝑦):(𝑥(Hom ‘𝐸)𝑦)⟶(((1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹))‘𝑥)(Hom ‘𝐶)((1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹))‘𝑦)))
4544ffnd 6704 . . . . 5 ((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) → (𝑥(2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹))𝑦) Fn (𝑥(Hom ‘𝐸)𝑦))
4619adantr 486 . . . . . . 7 ((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) → (1st ‘((1st𝑀)‘𝑋))(𝐸 Func 𝐶)(2nd ‘((1st𝑀)‘𝑋)))
471, 39, 40, 46, 42, 43funcf2 17960 . . . . . 6 ((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) → (𝑥(2nd ‘((1st𝑀)‘𝑋))𝑦):(𝑥(Hom ‘𝐸)𝑦)⟶(((1st ‘((1st𝑀)‘𝑋))‘𝑥)(Hom ‘𝐶)((1st ‘((1st𝑀)‘𝑋))‘𝑦)))
4847ffnd 6704 . . . . 5 ((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) → (𝑥(2nd ‘((1st𝑀)‘𝑋))𝑦) Fn (𝑥(Hom ‘𝐸)𝑦))
495ad2antrr 739 . . . . . . 7 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → 𝐶 ∈ Cat)
507ad2antrr 739 . . . . . . 7 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → 𝐷 ∈ Cat)
518ad2antrr 739 . . . . . . 7 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → 𝑋𝐵)
526ad2antrr 739 . . . . . . . . 9 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → (1st𝐹)(𝐸 Func 𝐷)(2nd𝐹))
531, 25, 52funcf1 17958 . . . . . . . 8 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → (1st𝐹):(Base‘𝐸)⟶(Base‘𝐷))
5442adantr 486 . . . . . . . 8 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → 𝑥 ∈ (Base‘𝐸))
5553, 54ffvelcdmd 7079 . . . . . . 7 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → ((1st𝐹)‘𝑥) ∈ (Base‘𝐷))
56 eqid 2760 . . . . . . 7 (Hom ‘𝐷) = (Hom ‘𝐷)
57 eqid 2760 . . . . . . 7 (Id‘𝐶) = (Id‘𝐶)
5843adantr 486 . . . . . . . 8 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → 𝑦 ∈ (Base‘𝐸))
5953, 58ffvelcdmd 7079 . . . . . . 7 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → ((1st𝐹)‘𝑦) ∈ (Base‘𝐷))
601, 39, 56, 52, 54, 58funcf2 17960 . . . . . . . 8 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → (𝑥(2nd𝐹)𝑦):(𝑥(Hom ‘𝐸)𝑦)⟶(((1st𝐹)‘𝑥)(Hom ‘𝐷)((1st𝐹)‘𝑦)))
61 simpr 490 . . . . . . . 8 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦))
6260, 61ffvelcdmd 7079 . . . . . . 7 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → ((𝑥(2nd𝐹)𝑦)‘𝑓) ∈ (((1st𝐹)‘𝑥)(Hom ‘𝐷)((1st𝐹)‘𝑦)))
634, 49, 50, 2, 51, 9, 25, 55, 56, 57, 59, 62diag12 18335 . . . . . 6 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → ((((1st𝐹)‘𝑥)(2nd ‘((1st𝐿)‘𝑋))((1st𝐹)‘𝑦))‘((𝑥(2nd𝐹)𝑦)‘𝑓)) = ((Id‘𝐶)‘𝑋))
643ad2antrr 739 . . . . . . 7 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → 𝐹 ∈ (𝐸 Func 𝐷))
6510ad2antrr 739 . . . . . . 7 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → ((1st𝐿)‘𝑋) ∈ (𝐷 Func 𝐶))
661, 64, 65, 54, 58, 39, 61cofu2 17978 . . . . . 6 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → ((𝑥(2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹))𝑦)‘𝑓) = ((((1st𝐹)‘𝑥)(2nd ‘((1st𝐿)‘𝑋))((1st𝐹)‘𝑦))‘((𝑥(2nd𝐹)𝑦)‘𝑓)))
6716ad2antrr 739 . . . . . . 7 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → 𝐸 ∈ Cat)
6815, 49, 67, 2, 51, 17, 1, 54, 39, 57, 58, 61diag12 18335 . . . . . 6 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → ((𝑥(2nd ‘((1st𝑀)‘𝑋))𝑦)‘𝑓) = ((Id‘𝐶)‘𝑋))
6963, 66, 683eqtr4d 2805 . . . . 5 (((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) ∧ 𝑓 ∈ (𝑥(Hom ‘𝐸)𝑦)) → ((𝑥(2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹))𝑦)‘𝑓) = ((𝑥(2nd ‘((1st𝑀)‘𝑋))𝑦)‘𝑓))
7045, 48, 69eqfnfvd 7026 . . . 4 ((𝜑 ∧ (𝑥 ∈ (Base‘𝐸) ∧ 𝑦 ∈ (Base‘𝐸))) → (𝑥(2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹))𝑦) = (𝑥(2nd ‘((1st𝑀)‘𝑋))𝑦))
7137, 38, 70eqfnovd 49797 . . 3 (𝜑 → (2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹)) = (2nd ‘((1st𝑀)‘𝑋)))
7236, 71opeq12d 4841 . 2 (𝜑 → ⟨(1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹)), (2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹))⟩ = ⟨(1st ‘((1st𝑀)‘𝑋)), (2nd ‘((1st𝑀)‘𝑋))⟩)
73 relfunc 17954 . . 3 Rel (𝐸 Func 𝐶)
74 1st2nd 8037 . . 3 ((Rel (𝐸 Func 𝐶) ∧ (((1st𝐿)‘𝑋) ∘func 𝐹) ∈ (𝐸 Func 𝐶)) → (((1st𝐿)‘𝑋) ∘func 𝐹) = ⟨(1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹)), (2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹))⟩)
7573, 11, 74sylancr 599 . 2 (𝜑 → (((1st𝐿)‘𝑋) ∘func 𝐹) = ⟨(1st ‘(((1st𝐿)‘𝑋) ∘func 𝐹)), (2nd ‘(((1st𝐿)‘𝑋) ∘func 𝐹))⟩)
76 1st2nd 8037 . . 3 ((Rel (𝐸 Func 𝐶) ∧ ((1st𝑀)‘𝑋) ∈ (𝐸 Func 𝐶)) → ((1st𝑀)‘𝑋) = ⟨(1st ‘((1st𝑀)‘𝑋)), (2nd ‘((1st𝑀)‘𝑋))⟩)
7773, 18, 76sylancr 599 . 2 (𝜑 → ((1st𝑀)‘𝑋) = ⟨(1st ‘((1st𝑀)‘𝑋)), (2nd ‘((1st𝑀)‘𝑋))⟩)
7872, 75, 773eqtr4d 2805 1 (𝜑 → (((1st𝐿)‘𝑋) ∘func 𝐹) = ((1st𝑀)‘𝑋))
Colors of variables:    wff setvar class
This proof depends on syntax axioms:  wi 4  wa 401   = wceq 1570  wcel 2145  cop 4590   class class class wbr 5103  Rel wrel 5660  cfv 6533  (class class class)co 7414  1st c1st 7985  2nd c2nd 7986  Basecbs 17304  Hom chom 17356  Catccat 17755  Idccid 17756   Func cfunc 17946  func ccofu 17948  Δfunccdiag 18303
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 2213  ax-ext 2732  ax-rep 5232  ax-sep 5251  ax-nul 5263  ax-pow 5330  ax-pr 5398  ax-un 7737  ax-cnex 11183  ax-resscn 11184  ax-1cn 11185  ax-icn 11186  ax-addcl 11187  ax-addrcl 11188  ax-mulcl 11189  ax-mulrcl 11190  ax-mulcom 11191  ax-addass 11192  ax-mulass 11193  ax-distr 11194  ax-i2m1 11195  ax-1ne0 11196  ax-1rid 11197  ax-rnegex 11198  ax-rrecex 11199  ax-cnre 11200  ax-pre-lttri 11201  ax-pre-lttrn 11202  ax-pre-ltadd 11203  ax-pre-mulgt0 11204
This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3or 1104  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2564  df-eu 2594  df-clab 2739  df-cleq 2752  df-clel 2835  df-nfc 2909  df-ne 2956  df-nel 3062  df-ral 3077  df-rex 3087  df-rmo 3365  df-reu 3366  df-rab 3413  df-v 3452  df-sbc 3740  df-csb 3848  df-dif 3902  df-un 3904  df-in 3906  df-ss 3916  df-pss 3919  df-nul 4280  df-if 4483  df-pw 4559  df-sn 4585  df-pr 4587  df-tp 4589  df-op 4591  df-uni 4868  df-iun 4953  df-br 5104  df-opab 5168  df-mpt 5187  df-tr 5213  df-id 5550  df-eprel 5555  df-po 5563  df-so 5564  df-fr 5608  df-we 5610  df-xp 5661  df-rel 5662  df-cnv 5663  df-co 5664  df-dm 5665  df-rn 5666  df-res 5667  df-ima 5668  df-pred 6299  df-ord 6360  df-on 6361  df-lim 6362  df-suc 6363  df-iota 6489  df-fun 6535  df-fn 6536  df-f 6537  df-f1 6538  df-fo 6539  df-f1o 6540  df-fv 6541  df-riota 7371  df-ov 7417  df-oprab 7418  df-mpo 7419  df-om 7864  df-1st 7987  df-2nd 7988  df-frecs 8281  df-wrecs 8312  df-recs 8361  df-rdg 8400  df-1o 8458  df-er 8699  df-map 8831  df-ixp 8908  df-en 8956  df-dom 8957  df-sdom 8958  df-fin 8959  df-pnf 11272  df-mnf 11273  df-xr 11274  df-ltxr 11275  df-le 11276  df-sub 11470  df-neg 11471  df-nn 12261  df-2 12330  df-3 12331  df-4 12332  df-5 12333  df-6 12334  df-7 12335  df-8 12336  df-9 12337  df-n0 12532  df-z 12619  df-dec 12740  df-uz 12891  df-fz 13565  df-struct 17242  df-slot 17277  df-ndx 17289  df-base 17305  df-hom 17369  df-cco 17370  df-cat 17759  df-cid 17760  df-func 17950  df-cofu 17952  df-nat 18038  df-fuc 18039  df-xpc 18263  df-1stf 18264  df-curf 18305  df-diag 18307
This theorem is used by:  prcofdiag  50323
  Copyright terms: Public domain W3C validator