Theorem exmidfodomrlemim 6764

Description: Excluded middle implies the existence of a mapping from any set onto any inhabited set that it dominates. Proposition 1.1 of [PradicBrown2022], p. 2. (Contributed by Jim Kingdon, 1-Jul-2022.)

Assertion

Ref	Expression
exmidfodomrlemim	⊢ (EXMID → ∀𝑥∀𝑦((∃𝑧 𝑧 ∈ 𝑦 ∧ 𝑦 ≼ 𝑥) → ∃𝑓 𝑓:𝑥–onto→𝑦))

Distinct variable groups:   𝑥,𝑓,𝑧   𝑦,𝑓,𝑧

Proof of Theorem exmidfodomrlemim

Dummy variables 𝑔 𝑢 𝑣 𝑤 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		brdomi 6412	. . . . 5 ⊢ (𝑦 ≼ 𝑥 → ∃𝑔 𝑔:𝑦–1-1→𝑥)
2	1	ad2antll 475	. . . 4 ⊢ ((EXMID ∧ (∃𝑧 𝑧 ∈ 𝑦 ∧ 𝑦 ≼ 𝑥)) → ∃𝑔 𝑔:𝑦–1-1→𝑥)
3		df-f1 4983	. . . . . . . . . . . . . . . . 17 ⊢ (𝑔:𝑦–1-1→𝑥 ↔ (𝑔:𝑦⟶𝑥 ∧ Fun ◡𝑔))
4	3	simprbi 269	. . . . . . . . . . . . . . . 16 ⊢ (𝑔:𝑦–1-1→𝑥 → Fun ◡𝑔)
5		vex 2618	. . . . . . . . . . . . . . . . . 18 ⊢ 𝑧 ∈ V
6	5	fconst 5163	. . . . . . . . . . . . . . . . 17 ⊢ ((𝑥 ∖ ran 𝑔) × {𝑧}):(𝑥 ∖ ran 𝑔)⟶{𝑧}
7		ffun 5126	. . . . . . . . . . . . . . . . 17 ⊢ (((𝑥 ∖ ran 𝑔) × {𝑧}):(𝑥 ∖ ran 𝑔)⟶{𝑧} → Fun ((𝑥 ∖ ran 𝑔) × {𝑧}))
8	6, 7	ax-mp 7	. . . . . . . . . . . . . . . 16 ⊢ Fun ((𝑥 ∖ ran 𝑔) × {𝑧})
9	4, 8	jctir 306	. . . . . . . . . . . . . . 15 ⊢ (𝑔:𝑦–1-1→𝑥 → (Fun ◡𝑔 ∧ Fun ((𝑥 ∖ ran 𝑔) × {𝑧})))
10		df-rn 4421	. . . . . . . . . . . . . . . . . 18 ⊢ ran 𝑔 = dom ◡𝑔
11	10	eqcomi 2089	. . . . . . . . . . . . . . . . 17 ⊢ dom ◡𝑔 = ran 𝑔
12	5	snm 3543	. . . . . . . . . . . . . . . . . 18 ⊢ ∃𝑤 𝑤 ∈ {𝑧}
13		dmxpm 4623	. . . . . . . . . . . . . . . . . 18 ⊢ (∃𝑤 𝑤 ∈ {𝑧} → dom ((𝑥 ∖ ran 𝑔) × {𝑧}) = (𝑥 ∖ ran 𝑔))
14	12, 13	ax-mp 7	. . . . . . . . . . . . . . . . 17 ⊢ dom ((𝑥 ∖ ran 𝑔) × {𝑧}) = (𝑥 ∖ ran 𝑔)
15	11, 14	ineq12i 3188	. . . . . . . . . . . . . . . 16 ⊢ (dom ◡𝑔 ∩ dom ((𝑥 ∖ ran 𝑔) × {𝑧})) = (ran 𝑔 ∩ (𝑥 ∖ ran 𝑔))
16		disjdif 3343	. . . . . . . . . . . . . . . 16 ⊢ (ran 𝑔 ∩ (𝑥 ∖ ran 𝑔)) = ∅
17	15, 16	eqtri 2105	. . . . . . . . . . . . . . 15 ⊢ (dom ◡𝑔 ∩ dom ((𝑥 ∖ ran 𝑔) × {𝑧})) = ∅
18		funun 5020	. . . . . . . . . . . . . . 15 ⊢ (((Fun ◡𝑔 ∧ Fun ((𝑥 ∖ ran 𝑔) × {𝑧})) ∧ (dom ◡𝑔 ∩ dom ((𝑥 ∖ ran 𝑔) × {𝑧})) = ∅) → Fun (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})))
19	9, 17, 18	sylancl 404	. . . . . . . . . . . . . 14 ⊢ (𝑔:𝑦–1-1→𝑥 → Fun (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})))
20	19	adantl 271	. . . . . . . . . . . . 13 ⊢ (((EXMID ∧ 𝑧 ∈ 𝑦) ∧ 𝑔:𝑦–1-1→𝑥) → Fun (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})))
21		f1rn 5174	. . . . . . . . . . . . . . . 16 ⊢ (𝑔:𝑦–1-1→𝑥 → ran 𝑔 ⊆ 𝑥)
22	21	adantl 271	. . . . . . . . . . . . . . 15 ⊢ (((EXMID ∧ 𝑧 ∈ 𝑦) ∧ 𝑔:𝑦–1-1→𝑥) → ran 𝑔 ⊆ 𝑥)
23		exmidexmid 4004	. . . . . . . . . . . . . . . . 17 ⊢ (EXMID → DECID 𝑢 ∈ ran 𝑔)
24	23	ralrimivw 2443	. . . . . . . . . . . . . . . 16 ⊢ (EXMID → ∀𝑢 ∈ 𝑥 DECID 𝑢 ∈ ran 𝑔)
25	24	ad2antrr 472	. . . . . . . . . . . . . . 15 ⊢ (((EXMID ∧ 𝑧 ∈ 𝑦) ∧ 𝑔:𝑦–1-1→𝑥) → ∀𝑢 ∈ 𝑥 DECID 𝑢 ∈ ran 𝑔)
26		undifdcss 6579	. . . . . . . . . . . . . . 15 ⊢ (𝑥 = (ran 𝑔 ∪ (𝑥 ∖ ran 𝑔)) ↔ (ran 𝑔 ⊆ 𝑥 ∧ ∀𝑢 ∈ 𝑥 DECID 𝑢 ∈ ran 𝑔))
27	22, 25, 26	sylanbrc 408	. . . . . . . . . . . . . 14 ⊢ (((EXMID ∧ 𝑧 ∈ 𝑦) ∧ 𝑔:𝑦–1-1→𝑥) → 𝑥 = (ran 𝑔 ∪ (𝑥 ∖ ran 𝑔)))
28		dmun 4610	. . . . . . . . . . . . . . 15 ⊢ dom (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) = (dom ◡𝑔 ∪ dom ((𝑥 ∖ ran 𝑔) × {𝑧}))
29	10	uneq1i 3139	. . . . . . . . . . . . . . 15 ⊢ (ran 𝑔 ∪ dom ((𝑥 ∖ ran 𝑔) × {𝑧})) = (dom ◡𝑔 ∪ dom ((𝑥 ∖ ran 𝑔) × {𝑧}))
30	14	uneq2i 3140	. . . . . . . . . . . . . . 15 ⊢ (ran 𝑔 ∪ dom ((𝑥 ∖ ran 𝑔) × {𝑧})) = (ran 𝑔 ∪ (𝑥 ∖ ran 𝑔))
31	28, 29, 30	3eqtr2i 2111	. . . . . . . . . . . . . 14 ⊢ dom (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) = (ran 𝑔 ∪ (𝑥 ∖ ran 𝑔))
32	27, 31	syl6reqr 2136	. . . . . . . . . . . . 13 ⊢ (((EXMID ∧ 𝑧 ∈ 𝑦) ∧ 𝑔:𝑦–1-1→𝑥) → dom (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) = 𝑥)
33		df-fn 4981	. . . . . . . . . . . . 13 ⊢ ((◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) Fn 𝑥 ↔ (Fun (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) ∧ dom (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) = 𝑥))
34	20, 32, 33	sylanbrc 408	. . . . . . . . . . . 12 ⊢ (((EXMID ∧ 𝑧 ∈ 𝑦) ∧ 𝑔:𝑦–1-1→𝑥) → (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) Fn 𝑥)
35		rnun 4803	. . . . . . . . . . . . 13 ⊢ ran (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) = (ran ◡𝑔 ∪ ran ((𝑥 ∖ ran 𝑔) × {𝑧}))
36		dfdm4 4595	. . . . . . . . . . . . . . . 16 ⊢ dom 𝑔 = ran ◡𝑔
37		f1dm 5178	. . . . . . . . . . . . . . . 16 ⊢ (𝑔:𝑦–1-1→𝑥 → dom 𝑔 = 𝑦)
38	36, 37	syl5eqr 2131	. . . . . . . . . . . . . . 15 ⊢ (𝑔:𝑦–1-1→𝑥 → ran ◡𝑔 = 𝑦)
39	38	uneq1d 3142	. . . . . . . . . . . . . 14 ⊢ (𝑔:𝑦–1-1→𝑥 → (ran ◡𝑔 ∪ ran ((𝑥 ∖ ran 𝑔) × {𝑧})) = (𝑦 ∪ ran ((𝑥 ∖ ran 𝑔) × {𝑧})))
40		exmidexmid 4004	. . . . . . . . . . . . . . . . . 18 ⊢ (EXMID → DECID ∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔))
41		exmiddc 780	. . . . . . . . . . . . . . . . . 18 ⊢ (DECID ∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔) → (∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔) ∨ ¬ ∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔)))
42	40, 41	syl 14	. . . . . . . . . . . . . . . . 17 ⊢ (EXMID → (∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔) ∨ ¬ ∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔)))
43		rnxpm 4823	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔) → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) = {𝑧})
44	43	adantr 270	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔) ∧ 𝑧 ∈ 𝑦) → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) = {𝑧})
45		snssi 3564	. . . . . . . . . . . . . . . . . . . . 21 ⊢ (𝑧 ∈ 𝑦 → {𝑧} ⊆ 𝑦)
46	45	adantl 271	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔) ∧ 𝑧 ∈ 𝑦) → {𝑧} ⊆ 𝑦)
47	44, 46	eqsstrd 3049	. . . . . . . . . . . . . . . . . . 19 ⊢ ((∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔) ∧ 𝑧 ∈ 𝑦) → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) ⊆ 𝑦)
48	47	ex 113	. . . . . . . . . . . . . . . . . 18 ⊢ (∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔) → (𝑧 ∈ 𝑦 → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) ⊆ 𝑦))
49		notm0 3292	. . . . . . . . . . . . . . . . . . 19 ⊢ (¬ ∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔) ↔ (𝑥 ∖ ran 𝑔) = ∅)
50		xpeq1 4424	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ ((𝑥 ∖ ran 𝑔) = ∅ → ((𝑥 ∖ ran 𝑔) × {𝑧}) = (∅ × {𝑧}))
51		0xp 4485	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ (∅ × {𝑧}) = ∅
52	50, 51	syl6eq 2133	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ ((𝑥 ∖ ran 𝑔) = ∅ → ((𝑥 ∖ ran 𝑔) × {𝑧}) = ∅)
53	52	rneqd 4631	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ((𝑥 ∖ ran 𝑔) = ∅ → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) = ran ∅)
54		rn0 4656	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ran ∅ = ∅
55	53, 54	syl6eq 2133	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((𝑥 ∖ ran 𝑔) = ∅ → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) = ∅)
56		0ss 3309	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ∅ ⊆ 𝑦
57	55, 56	syl6eqss 3065	. . . . . . . . . . . . . . . . . . . 20 ⊢ ((𝑥 ∖ ran 𝑔) = ∅ → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) ⊆ 𝑦)
58	57	a1d 22	. . . . . . . . . . . . . . . . . . 19 ⊢ ((𝑥 ∖ ran 𝑔) = ∅ → (𝑧 ∈ 𝑦 → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) ⊆ 𝑦))
59	49, 58	sylbi 119	. . . . . . . . . . . . . . . . . 18 ⊢ (¬ ∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔) → (𝑧 ∈ 𝑦 → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) ⊆ 𝑦))
60	48, 59	jaoi 669	. . . . . . . . . . . . . . . . 17 ⊢ ((∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔) ∨ ¬ ∃𝑣 𝑣 ∈ (𝑥 ∖ ran 𝑔)) → (𝑧 ∈ 𝑦 → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) ⊆ 𝑦))
61	42, 60	syl 14	. . . . . . . . . . . . . . . 16 ⊢ (EXMID → (𝑧 ∈ 𝑦 → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) ⊆ 𝑦))
62	61	imp 122	. . . . . . . . . . . . . . 15 ⊢ ((EXMID ∧ 𝑧 ∈ 𝑦) → ran ((𝑥 ∖ ran 𝑔) × {𝑧}) ⊆ 𝑦)
63		ssequn2 3162	. . . . . . . . . . . . . . 15 ⊢ (ran ((𝑥 ∖ ran 𝑔) × {𝑧}) ⊆ 𝑦 ↔ (𝑦 ∪ ran ((𝑥 ∖ ran 𝑔) × {𝑧})) = 𝑦)
64	62, 63	sylib 120	. . . . . . . . . . . . . 14 ⊢ ((EXMID ∧ 𝑧 ∈ 𝑦) → (𝑦 ∪ ran ((𝑥 ∖ ran 𝑔) × {𝑧})) = 𝑦)
65	39, 64	sylan9eqr 2139	. . . . . . . . . . . . 13 ⊢ (((EXMID ∧ 𝑧 ∈ 𝑦) ∧ 𝑔:𝑦–1-1→𝑥) → (ran ◡𝑔 ∪ ran ((𝑥 ∖ ran 𝑔) × {𝑧})) = 𝑦)
66	35, 65	syl5eq 2129	. . . . . . . . . . . 12 ⊢ (((EXMID ∧ 𝑧 ∈ 𝑦) ∧ 𝑔:𝑦–1-1→𝑥) → ran (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) = 𝑦)
67		df-fo 4984	. . . . . . . . . . . 12 ⊢ ((◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})):𝑥–onto→𝑦 ↔ ((◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) Fn 𝑥 ∧ ran (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) = 𝑦))
68	34, 66, 67	sylanbrc 408	. . . . . . . . . . 11 ⊢ (((EXMID ∧ 𝑧 ∈ 𝑦) ∧ 𝑔:𝑦–1-1→𝑥) → (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})):𝑥–onto→𝑦)
69		vex 2618	. . . . . . . . . . . . . 14 ⊢ 𝑔 ∈ V
70	69	cnvex 4932	. . . . . . . . . . . . 13 ⊢ ◡𝑔 ∈ V
71		vex 2618	. . . . . . . . . . . . . . 15 ⊢ 𝑥 ∈ V
72		difexg 3954	. . . . . . . . . . . . . . 15 ⊢ (𝑥 ∈ V → (𝑥 ∖ ran 𝑔) ∈ V)
73	71, 72	ax-mp 7	. . . . . . . . . . . . . 14 ⊢ (𝑥 ∖ ran 𝑔) ∈ V
74	5	snex 3993	. . . . . . . . . . . . . 14 ⊢ {𝑧} ∈ V
75	73, 74	xpex 4520	. . . . . . . . . . . . 13 ⊢ ((𝑥 ∖ ran 𝑔) × {𝑧}) ∈ V
76	70, 75	unex 4239	. . . . . . . . . . . 12 ⊢ (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) ∈ V
77		foeq1 5186	. . . . . . . . . . . 12 ⊢ (𝑓 = (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})) → (𝑓:𝑥–onto→𝑦 ↔ (◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})):𝑥–onto→𝑦))
78	76, 77	spcev 2706	. . . . . . . . . . 11 ⊢ ((◡𝑔 ∪ ((𝑥 ∖ ran 𝑔) × {𝑧})):𝑥–onto→𝑦 → ∃𝑓 𝑓:𝑥–onto→𝑦)
79	68, 78	syl 14	. . . . . . . . . 10 ⊢ (((EXMID ∧ 𝑧 ∈ 𝑦) ∧ 𝑔:𝑦–1-1→𝑥) → ∃𝑓 𝑓:𝑥–onto→𝑦)
80	79	an32s 533	. . . . . . . . 9 ⊢ (((EXMID ∧ 𝑔:𝑦–1-1→𝑥) ∧ 𝑧 ∈ 𝑦) → ∃𝑓 𝑓:𝑥–onto→𝑦)
81	80	ex 113	. . . . . . . 8 ⊢ ((EXMID ∧ 𝑔:𝑦–1-1→𝑥) → (𝑧 ∈ 𝑦 → ∃𝑓 𝑓:𝑥–onto→𝑦))
82	81	exlimdv 1744	. . . . . . 7 ⊢ ((EXMID ∧ 𝑔:𝑦–1-1→𝑥) → (∃𝑧 𝑧 ∈ 𝑦 → ∃𝑓 𝑓:𝑥–onto→𝑦))
83	82	imp 122	. . . . . 6 ⊢ (((EXMID ∧ 𝑔:𝑦–1-1→𝑥) ∧ ∃𝑧 𝑧 ∈ 𝑦) → ∃𝑓 𝑓:𝑥–onto→𝑦)
84	83	an32s 533	. . . . 5 ⊢ (((EXMID ∧ ∃𝑧 𝑧 ∈ 𝑦) ∧ 𝑔:𝑦–1-1→𝑥) → ∃𝑓 𝑓:𝑥–onto→𝑦)
85	84	adantlrr 467	. . . 4 ⊢ (((EXMID ∧ (∃𝑧 𝑧 ∈ 𝑦 ∧ 𝑦 ≼ 𝑥)) ∧ 𝑔:𝑦–1-1→𝑥) → ∃𝑓 𝑓:𝑥–onto→𝑦)
86	2, 85	exlimddv 1823	. . 3 ⊢ ((EXMID ∧ (∃𝑧 𝑧 ∈ 𝑦 ∧ 𝑦 ≼ 𝑥)) → ∃𝑓 𝑓:𝑥–onto→𝑦)
87	86	ex 113	. 2 ⊢ (EXMID → ((∃𝑧 𝑧 ∈ 𝑦 ∧ 𝑦 ≼ 𝑥) → ∃𝑓 𝑓:𝑥–onto→𝑦))
88	87	alrimivv 1800	1 ⊢ (EXMID → ∀𝑥∀𝑦((∃𝑧 𝑧 ∈ 𝑦 ∧ 𝑦 ≼ 𝑥) → ∃𝑓 𝑓:𝑥–onto→𝑦))

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 102   ∨ wo 662  DECID wdc 778  ∀wal 1285   = wceq 1287  ∃wex 1424   ∈ wcel 1436  ∀wral 2355  Vcvv 2615   ∖ cdif 2985   ∪ cun 2986   ∩ cin 2987   ⊆ wss 2988  ∅c0 3275  {csn 3431   class class class wbr 3820  EXMIDwem 4002   × cxp 4408  ^◡ccnv 4409  dom cdm 4410  ran crn 4411  Fun wfun 4972   Fn wfn 4973  ⟶wf 4974  –1-1→wf1 4975  –onto→wfo 4976   ≼ cdom 6402

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-in1 577  ax-in2 578  ax-io 663  ax-5 1379  ax-7 1380  ax-gen 1381  ax-ie1 1425  ax-ie2 1426  ax-8 1438  ax-10 1439  ax-11 1440  ax-i12 1441  ax-bndl 1442  ax-4 1443  ax-13 1447  ax-14 1448  ax-17 1462  ax-i9 1466  ax-ial 1470  ax-i5r 1471  ax-ext 2067  ax-sep 3931  ax-nul 3939  ax-pow 3983  ax-pr 4009  ax-un 4233

This theorem depends on definitions:  df-bi 115  df-dc 779  df-3an 924  df-tru 1290  df-fal 1293  df-nf 1393  df-sb 1690  df-eu 1948  df-mo 1949  df-clab 2072  df-cleq 2078  df-clel 2081  df-nfc 2214  df-ral 2360  df-rex 2361  df-rab 2364  df-v 2617  df-dif 2990  df-un 2992  df-in 2994  df-ss 3001  df-nul 3276  df-pw 3417  df-sn 3437  df-pr 3438  df-op 3440  df-uni 3637  df-br 3821  df-opab 3875  df-mpt 3876  df-exmid 4003  df-id 4093  df-xp 4416  df-rel 4417  df-cnv 4418  df-co 4419  df-dm 4420  df-rn 4421  df-fun 4980  df-fn 4981  df-f 4982  df-f1 4983  df-fo 4984  df-dom 6405

This theorem is referenced by:  exmidfodomr  6767