Theorem finexdc 7072

Description: Decidability of existence, over a finite set and defined by a decidable proposition. (Contributed by Jim Kingdon, 12-Jul-2022.)

Assertion

Ref	Expression
finexdc	⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) → DECID ∃𝑥 ∈ 𝐴 𝜑)

Distinct variable group:   𝑥,𝐴

Allowed substitution hint:   𝜑(𝑥)

Proof of Theorem finexdc

Dummy variables 𝑤 𝑦 𝑧 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		rexeq 2729	. . 3 ⊢ (𝑤 = ∅ → (∃𝑥 ∈ 𝑤 𝜑 ↔ ∃𝑥 ∈ ∅ 𝜑))
2	1	dcbid 843	. 2 ⊢ (𝑤 = ∅ → (DECID ∃𝑥 ∈ 𝑤 𝜑 ↔ DECID ∃𝑥 ∈ ∅ 𝜑))
3		rexeq 2729	. . 3 ⊢ (𝑤 = 𝑦 → (∃𝑥 ∈ 𝑤 𝜑 ↔ ∃𝑥 ∈ 𝑦 𝜑))
4	3	dcbid 843	. 2 ⊢ (𝑤 = 𝑦 → (DECID ∃𝑥 ∈ 𝑤 𝜑 ↔ DECID ∃𝑥 ∈ 𝑦 𝜑))
5		rexeq 2729	. . 3 ⊢ (𝑤 = (𝑦 ∪ {𝑧}) → (∃𝑥 ∈ 𝑤 𝜑 ↔ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑))
6	5	dcbid 843	. 2 ⊢ (𝑤 = (𝑦 ∪ {𝑧}) → (DECID ∃𝑥 ∈ 𝑤 𝜑 ↔ DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑))
7		rexeq 2729	. . 3 ⊢ (𝑤 = 𝐴 → (∃𝑥 ∈ 𝑤 𝜑 ↔ ∃𝑥 ∈ 𝐴 𝜑))
8	7	dcbid 843	. 2 ⊢ (𝑤 = 𝐴 → (DECID ∃𝑥 ∈ 𝑤 𝜑 ↔ DECID ∃𝑥 ∈ 𝐴 𝜑))
9		rex0 3509	. . . . 5 ⊢ ¬ ∃𝑥 ∈ ∅ 𝜑
10	9	olci 737	. . . 4 ⊢ (∃𝑥 ∈ ∅ 𝜑 ∨ ¬ ∃𝑥 ∈ ∅ 𝜑)
11		df-dc 840	. . . 4 ⊢ (DECID ∃𝑥 ∈ ∅ 𝜑 ↔ (∃𝑥 ∈ ∅ 𝜑 ∨ ¬ ∃𝑥 ∈ ∅ 𝜑))
12	10, 11	mpbir 146	. . 3 ⊢ DECID ∃𝑥 ∈ ∅ 𝜑
13	12	a1i 9	. 2 ⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) → DECID ∃𝑥 ∈ ∅ 𝜑)
14		simpr 110	. . . . . . . . 9 ⊢ ((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → [𝑧 / 𝑥]𝜑)
15		sbsbc 3032	. . . . . . . . . 10 ⊢ ([𝑧 / 𝑥]𝜑 ↔ [𝑧 / 𝑥]𝜑)
16		rexsns 3705	. . . . . . . . . 10 ⊢ (∃𝑥 ∈ {𝑧}𝜑 ↔ [𝑧 / 𝑥]𝜑)
17	15, 16	bitr4i 187	. . . . . . . . 9 ⊢ ([𝑧 / 𝑥]𝜑 ↔ ∃𝑥 ∈ {𝑧}𝜑)
18	14, 17	sylib 122	. . . . . . . 8 ⊢ ((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → ∃𝑥 ∈ {𝑧}𝜑)
19	18	olcd 739	. . . . . . 7 ⊢ ((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → (∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑))
20		rexun 3384	. . . . . . 7 ⊢ (∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ↔ (∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑))
21	19, 20	sylibr 134	. . . . . 6 ⊢ ((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)
22	21	orcd 738	. . . . 5 ⊢ ((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → (∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ∨ ¬ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑))
23		df-dc 840	. . . . 5 ⊢ (DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ↔ (∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ∨ ¬ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑))
24	22, 23	sylibr 134	. . . 4 ⊢ ((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ [𝑧 / 𝑥]𝜑) → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)
25		simpr 110	. . . . . . . . 9 ⊢ (((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ∃𝑥 ∈ 𝑦 𝜑) → ∃𝑥 ∈ 𝑦 𝜑)
26	25	orcd 738	. . . . . . . 8 ⊢ (((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ∃𝑥 ∈ 𝑦 𝜑) → (∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑))
27	26, 20	sylibr 134	. . . . . . 7 ⊢ (((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ∃𝑥 ∈ 𝑦 𝜑) → ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)
28	27	orcd 738	. . . . . 6 ⊢ (((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ∃𝑥 ∈ 𝑦 𝜑) → (∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ∨ ¬ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑))
29	28, 23	sylibr 134	. . . . 5 ⊢ (((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ∃𝑥 ∈ 𝑦 𝜑) → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)
30		simpr 110	. . . . . . . . 9 ⊢ (((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → ¬ ∃𝑥 ∈ 𝑦 𝜑)
31		simpr 110	. . . . . . . . . . 11 ⊢ ((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) → ¬ [𝑧 / 𝑥]𝜑)
32	17	notbii 672	. . . . . . . . . . 11 ⊢ (¬ [𝑧 / 𝑥]𝜑 ↔ ¬ ∃𝑥 ∈ {𝑧}𝜑)
33	31, 32	sylib 122	. . . . . . . . . 10 ⊢ ((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) → ¬ ∃𝑥 ∈ {𝑧}𝜑)
34	33	adantr 276	. . . . . . . . 9 ⊢ (((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → ¬ ∃𝑥 ∈ {𝑧}𝜑)
35		ioran 757	. . . . . . . . 9 ⊢ (¬ (∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑) ↔ (¬ ∃𝑥 ∈ 𝑦 𝜑 ∧ ¬ ∃𝑥 ∈ {𝑧}𝜑))
36	30, 34, 35	sylanbrc 417	. . . . . . . 8 ⊢ (((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → ¬ (∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑))
37	20	notbii 672	. . . . . . . 8 ⊢ (¬ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ↔ ¬ (∃𝑥 ∈ 𝑦 𝜑 ∨ ∃𝑥 ∈ {𝑧}𝜑))
38	36, 37	sylibr 134	. . . . . . 7 ⊢ (((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → ¬ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)
39	38	olcd 739	. . . . . 6 ⊢ (((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → (∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑 ∨ ¬ ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑))
40	39, 23	sylibr 134	. . . . 5 ⊢ (((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) ∧ ¬ ∃𝑥 ∈ 𝑦 𝜑) → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)
41		exmiddc 841	. . . . . 6 ⊢ (DECID ∃𝑥 ∈ 𝑦 𝜑 → (∃𝑥 ∈ 𝑦 𝜑 ∨ ¬ ∃𝑥 ∈ 𝑦 𝜑))
42	41	ad2antlr 489	. . . . 5 ⊢ ((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) → (∃𝑥 ∈ 𝑦 𝜑 ∨ ¬ ∃𝑥 ∈ 𝑦 𝜑))
43	29, 40, 42	mpjaodan 803	. . . 4 ⊢ ((((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) ∧ ¬ [𝑧 / 𝑥]𝜑) → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)
44		simplrr 536	. . . . . . 7 ⊢ (((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → 𝑧 ∈ (𝐴 ∖ 𝑦))
45	44	eldifad 3208	. . . . . 6 ⊢ (((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → 𝑧 ∈ 𝐴)
46		simp-4r 542	. . . . . 6 ⊢ (((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → ∀𝑥 ∈ 𝐴 DECID 𝜑)
47		nfs1v 1990	. . . . . . . 8 ⊢ Ⅎ𝑥[𝑧 / 𝑥]𝜑
48	47	nfdc 1705	. . . . . . 7 ⊢ Ⅎ𝑥DECID [𝑧 / 𝑥]𝜑
49		sbequ12 1817	. . . . . . . 8 ⊢ (𝑥 = 𝑧 → (𝜑 ↔ [𝑧 / 𝑥]𝜑))
50	49	dcbid 843	. . . . . . 7 ⊢ (𝑥 = 𝑧 → (DECID 𝜑 ↔ DECID [𝑧 / 𝑥]𝜑))
51	48, 50	rspc 2901	. . . . . 6 ⊢ (𝑧 ∈ 𝐴 → (∀𝑥 ∈ 𝐴 DECID 𝜑 → DECID [𝑧 / 𝑥]𝜑))
52	45, 46, 51	sylc 62	. . . . 5 ⊢ (((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → DECID [𝑧 / 𝑥]𝜑)
53		exmiddc 841	. . . . 5 ⊢ (DECID [𝑧 / 𝑥]𝜑 → ([𝑧 / 𝑥]𝜑 ∨ ¬ [𝑧 / 𝑥]𝜑))
54	52, 53	syl 14	. . . 4 ⊢ (((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → ([𝑧 / 𝑥]𝜑 ∨ ¬ [𝑧 / 𝑥]𝜑))
55	24, 43, 54	mpjaodan 803	. . 3 ⊢ (((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) ∧ DECID ∃𝑥 ∈ 𝑦 𝜑) → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑)
56	55	ex 115	. 2 ⊢ ((((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) ∧ 𝑦 ∈ Fin) ∧ (𝑦 ⊆ 𝐴 ∧ 𝑧 ∈ (𝐴 ∖ 𝑦))) → (DECID ∃𝑥 ∈ 𝑦 𝜑 → DECID ∃𝑥 ∈ (𝑦 ∪ {𝑧})𝜑))
57		simpl 109	. 2 ⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) → 𝐴 ∈ Fin)
58	2, 4, 6, 8, 13, 56, 57	findcard2sd 7062	1 ⊢ ((𝐴 ∈ Fin ∧ ∀𝑥 ∈ 𝐴 DECID 𝜑) → DECID ∃𝑥 ∈ 𝐴 𝜑)

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 104   ∨ wo 713  DECID wdc 839   = wceq 1395  [wsb 1808   ∈ wcel 2200  ∀wral 2508  ∃wrex 2509  [wsbc 3028   ∖ cdif 3194   ∪ cun 3195   ⊆ wss 3197  ∅c0 3491  {csn 3666  Fincfn 6895

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-13 2202  ax-14 2203  ax-ext 2211  ax-coll 4199  ax-sep 4202  ax-nul 4210  ax-pow 4258  ax-pr 4293  ax-un 4524  ax-setind 4629  ax-iinf 4680

This theorem depends on definitions:  df-bi 117  df-dc 840  df-3or 1003  df-3an 1004  df-tru 1398  df-fal 1401  df-nf 1507  df-sb 1809  df-eu 2080  df-mo 2081  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-ne 2401  df-ral 2513  df-rex 2514  df-reu 2515  df-rab 2517  df-v 2801  df-sbc 3029  df-csb 3125  df-dif 3199  df-un 3201  df-in 3203  df-ss 3210  df-nul 3492  df-if 3603  df-pw 3651  df-sn 3672  df-pr 3673  df-op 3675  df-uni 3889  df-int 3924  df-iun 3967  df-br 4084  df-opab 4146  df-mpt 4147  df-tr 4183  df-id 4384  df-iord 4457  df-on 4459  df-suc 4462  df-iom 4683  df-xp 4725  df-rel 4726  df-cnv 4727  df-co 4728  df-dm 4729  df-rn 4730  df-res 4731  df-ima 4732  df-iota 5278  df-fun 5320  df-fn 5321  df-f 5322  df-f1 5323  df-fo 5324  df-f1o 5325  df-fv 5326  df-er 6688  df-en 6896  df-fin 6898

This theorem is referenced by:  dfrex2fin  7073  nninfwlpoimlemg  7350  nninfwlpoimlemginf  7351  4sqleminfi  12928