Theorem rdgssun 38301

Description: In a recursive definition where each step expands on the previous one using a union, every previous step is a subset of every later step. (Contributed by ML, 1-Apr-2022.)

Hypotheses

Ref	Expression
rdgssun.1	⊢ 𝐹 = (𝑤 ∈ V ↦ (𝑤 ∪ 𝐵))
rdgssun.2	⊢ 𝐵 ∈ V

Assertion

Ref	Expression
rdgssun	⊢ ((𝑋 ∈ On ∧ 𝑌 ∈ 𝑋) → (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋))

Distinct variable groups:   𝑤,𝐴   𝑤,𝑌

Allowed substitution hints:   𝐵(𝑤)   𝐹(𝑤)   𝑋(𝑤)

Proof of Theorem rdgssun

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

Step	Hyp	Ref	Expression
1		nfsbc1v 3759	. . . . . . . . . . . 12 ⊢ Ⅎ𝑥[∅ / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)
2		0ex 5261	. . . . . . . . . . . 12 ⊢ ∅ ∈ V
3		rzal 4450	. . . . . . . . . . . . 13 ⊢ (𝑥 = ∅ → ∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥))
4		sbceq1a 3750	. . . . . . . . . . . . 13 ⊢ (𝑥 = ∅ → (∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) ↔ [∅ / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)))
5	3, 4	mpbid 235	. . . . . . . . . . . 12 ⊢ (𝑥 = ∅ → [∅ / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥))
6	1, 2, 5	vtoclef 3525	. . . . . . . . . . 11 ⊢ [∅ / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)
7		vex 3455	. . . . . . . . . . . . . . . 16 ⊢ 𝑦 ∈ V
8	7	elsuc 6435	. . . . . . . . . . . . . . 15 ⊢ (𝑦 ∈ suc 𝑥 ↔ (𝑦 ∈ 𝑥 ∨ 𝑦 = 𝑥))
9		ssun1 4124	. . . . . . . . . . . . . . . . . . . 20 ⊢ (rec(𝐹, 𝐴)‘𝑥) ⊆ ((rec(𝐹, 𝐴)‘𝑥) ∪ ⦋(rec(𝐹, 𝐴)‘𝑥) / 𝑤⦌𝐵)
10		fvex 6898	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (rec(𝐹, 𝐴)‘𝑥) ∈ V
11		rdgssun.2	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ 𝐵 ∈ V
12	11	csbex 5265	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ ⦋(rec(𝐹, 𝐴)‘𝑥) / 𝑤⦌𝐵 ∈ V
13	10, 12	unex 7761	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((rec(𝐹, 𝐴)‘𝑥) ∪ ⦋(rec(𝐹, 𝐴)‘𝑥) / 𝑤⦌𝐵) ∈ V
14		nfcv 2923	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ Ⅎ𝑤𝐴
15		nfcv 2923	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ Ⅎ𝑤𝑥
16		rdgssun.1	. . . . . . . . . . . . . . . . . . . . . . . . . 26 ⊢ 𝐹 = (𝑤 ∈ V ↦ (𝑤 ∪ 𝐵))
17		nfmpt1 5204	. . . . . . . . . . . . . . . . . . . . . . . . . 26 ⊢ Ⅎ𝑤(𝑤 ∈ V ↦ (𝑤 ∪ 𝐵))
18	16, 17	nfcxfr 2921	. . . . . . . . . . . . . . . . . . . . . . . . 25 ⊢ Ⅎ𝑤𝐹
19	18, 14	nfrdg 8422	. . . . . . . . . . . . . . . . . . . . . . . 24 ⊢ Ⅎ𝑤rec(𝐹, 𝐴)
20	19, 15	nffv 6895	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ Ⅎ𝑤(rec(𝐹, 𝐴)‘𝑥)
21	20	nfcsb1 3870	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ Ⅎ𝑤⦋(rec(𝐹, 𝐴)‘𝑥) / 𝑤⦌𝐵
22	20, 21	nfun 4117	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ Ⅎ𝑤((rec(𝐹, 𝐴)‘𝑥) ∪ ⦋(rec(𝐹, 𝐴)‘𝑥) / 𝑤⦌𝐵)
23		rdgeq1 8419	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (𝐹 = (𝑤 ∈ V ↦ (𝑤 ∪ 𝐵)) → rec(𝐹, 𝐴) = rec((𝑤 ∈ V ↦ (𝑤 ∪ 𝐵)), 𝐴))
24	16, 23	ax-mp 5	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ rec(𝐹, 𝐴) = rec((𝑤 ∈ V ↦ (𝑤 ∪ 𝐵)), 𝐴)
25		id 23	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (𝑤 = (rec(𝐹, 𝐴)‘𝑥) → 𝑤 = (rec(𝐹, 𝐴)‘𝑥))
26		csbeq1a 3861	. . . . . . . . . . . . . . . . . . . . . . 23 ⊢ (𝑤 = (rec(𝐹, 𝐴)‘𝑥) → 𝐵 = ⦋(rec(𝐹, 𝐴)‘𝑥) / 𝑤⦌𝐵)
27	25, 26	uneq12d 4116	. . . . . . . . . . . . . . . . . . . . . 22 ⊢ (𝑤 = (rec(𝐹, 𝐴)‘𝑥) → (𝑤 ∪ 𝐵) = ((rec(𝐹, 𝐴)‘𝑥) ∪ ⦋(rec(𝐹, 𝐴)‘𝑥) / 𝑤⦌𝐵))
28	14, 15, 22, 24, 27	rdgsucmptf 8436	. . . . . . . . . . . . . . . . . . . . 21 ⊢ ((𝑥 ∈ On ∧ ((rec(𝐹, 𝐴)‘𝑥) ∪ ⦋(rec(𝐹, 𝐴)‘𝑥) / 𝑤⦌𝐵) ∈ V) → (rec(𝐹, 𝐴)‘suc 𝑥) = ((rec(𝐹, 𝐴)‘𝑥) ∪ ⦋(rec(𝐹, 𝐴)‘𝑥) / 𝑤⦌𝐵))
29	13, 28	mpan2 704	. . . . . . . . . . . . . . . . . . . 20 ⊢ (𝑥 ∈ On → (rec(𝐹, 𝐴)‘suc 𝑥) = ((rec(𝐹, 𝐴)‘𝑥) ∪ ⦋(rec(𝐹, 𝐴)‘𝑥) / 𝑤⦌𝐵))
30	9, 29	sseqtrrid 3974	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑥 ∈ On → (rec(𝐹, 𝐴)‘𝑥) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥))
31		sstr2 3938	. . . . . . . . . . . . . . . . . . 19 ⊢ ((rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) → ((rec(𝐹, 𝐴)‘𝑥) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥) → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥)))
32	30, 31	syl5com 32	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑥 ∈ On → ((rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥)))
33	32	imim2d 58	. . . . . . . . . . . . . . . . 17 ⊢ (𝑥 ∈ On → ((𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)) → (𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥))))
34	33	imp 412	. . . . . . . . . . . . . . . 16 ⊢ ((𝑥 ∈ On ∧ (𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥))) → (𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥)))
35		fveq2 6885	. . . . . . . . . . . . . . . . . . 19 ⊢ (𝑦 = 𝑥 → (rec(𝐹, 𝐴)‘𝑦) = (rec(𝐹, 𝐴)‘𝑥))
36	35	sseq1d 3962	. . . . . . . . . . . . . . . . . 18 ⊢ (𝑦 = 𝑥 → ((rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥) ↔ (rec(𝐹, 𝐴)‘𝑥) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥)))
37	30, 36	syl5ibrcom 250	. . . . . . . . . . . . . . . . 17 ⊢ (𝑥 ∈ On → (𝑦 = 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥)))
38	37	adantr 486	. . . . . . . . . . . . . . . 16 ⊢ ((𝑥 ∈ On ∧ (𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥))) → (𝑦 = 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥)))
39	34, 38	jaod 873	. . . . . . . . . . . . . . 15 ⊢ ((𝑥 ∈ On ∧ (𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥))) → ((𝑦 ∈ 𝑥 ∨ 𝑦 = 𝑥) → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥)))
40	8, 39	biimtrid 245	. . . . . . . . . . . . . 14 ⊢ ((𝑥 ∈ On ∧ (𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥))) → (𝑦 ∈ suc 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥)))
41	40	ex 418	. . . . . . . . . . . . 13 ⊢ (𝑥 ∈ On → ((𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)) → (𝑦 ∈ suc 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥))))
42	41	ralimdv2 3172	. . . . . . . . . . . 12 ⊢ (𝑥 ∈ On → (∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) → ∀𝑦 ∈ suc 𝑥(rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥)))
43		df-sbc 3740	. . . . . . . . . . . . 13 ⊢ ([suc 𝑥 / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) ↔ suc 𝑥 ∈ {𝑥 ∣ ∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)})
44		vex 3455	. . . . . . . . . . . . . . 15 ⊢ 𝑥 ∈ V
45	44	sucex 7820	. . . . . . . . . . . . . 14 ⊢ suc 𝑥 ∈ V
46		fveq2 6885	. . . . . . . . . . . . . . . 16 ⊢ (𝑧 = suc 𝑥 → (rec(𝐹, 𝐴)‘𝑧) = (rec(𝐹, 𝐴)‘suc 𝑥))
47	46	sseq2d 3963	. . . . . . . . . . . . . . 15 ⊢ (𝑧 = suc 𝑥 → ((rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧) ↔ (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥)))
48	47	raleqbi1dv 3330	. . . . . . . . . . . . . 14 ⊢ (𝑧 = suc 𝑥 → (∀𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧) ↔ ∀𝑦 ∈ suc 𝑥(rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥)))
49		fveq2 6885	. . . . . . . . . . . . . . . . 17 ⊢ (𝑥 = 𝑧 → (rec(𝐹, 𝐴)‘𝑥) = (rec(𝐹, 𝐴)‘𝑧))
50	49	sseq2d 3963	. . . . . . . . . . . . . . . 16 ⊢ (𝑥 = 𝑧 → ((rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) ↔ (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧)))
51	50	raleqbi1dv 3330	. . . . . . . . . . . . . . 15 ⊢ (𝑥 = 𝑧 → (∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) ↔ ∀𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧)))
52	51	cbvabv 2831	. . . . . . . . . . . . . 14 ⊢ {𝑥 ∣ ∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)} = {𝑧 ∣ ∀𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧)}
53	45, 48, 52	elab2 3636	. . . . . . . . . . . . 13 ⊢ (suc 𝑥 ∈ {𝑥 ∣ ∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)} ↔ ∀𝑦 ∈ suc 𝑥(rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥))
54	43, 53	bitri 278	. . . . . . . . . . . 12 ⊢ ([suc 𝑥 / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) ↔ ∀𝑦 ∈ suc 𝑥(rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘suc 𝑥))
55	42, 54	imbitrrdi 255	. . . . . . . . . . 11 ⊢ (𝑥 ∈ On → (∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) → [suc 𝑥 / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)))
56		ssiun2 5006	. . . . . . . . . . . . . . . 16 ⊢ (𝑦 ∈ 𝑧 → (rec(𝐹, 𝐴)‘𝑦) ⊆ ∪ 𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦))
57	56	adantl 487	. . . . . . . . . . . . . . 15 ⊢ ((Lim 𝑧 ∧ 𝑦 ∈ 𝑧) → (rec(𝐹, 𝐴)‘𝑦) ⊆ ∪ 𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦))
58		vex 3455	. . . . . . . . . . . . . . . . 17 ⊢ 𝑧 ∈ V
59		rdglim2a 8441	. . . . . . . . . . . . . . . . 17 ⊢ ((𝑧 ∈ V ∧ Lim 𝑧) → (rec(𝐹, 𝐴)‘𝑧) = ∪ 𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦))
60	58, 59	mpan 703	. . . . . . . . . . . . . . . 16 ⊢ (Lim 𝑧 → (rec(𝐹, 𝐴)‘𝑧) = ∪ 𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦))
61	60	adantr 486	. . . . . . . . . . . . . . 15 ⊢ ((Lim 𝑧 ∧ 𝑦 ∈ 𝑧) → (rec(𝐹, 𝐴)‘𝑧) = ∪ 𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦))
62	57, 61	sseqtrrd 3968	. . . . . . . . . . . . . 14 ⊢ ((Lim 𝑧 ∧ 𝑦 ∈ 𝑧) → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧))
63	62	ralrimiva 3155	. . . . . . . . . . . . 13 ⊢ (Lim 𝑧 → ∀𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧))
64		df-sbc 3740	. . . . . . . . . . . . . . 15 ⊢ ([𝑧 / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) ↔ 𝑧 ∈ {𝑥 ∣ ∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)})
65	52	eleq2i 2853	. . . . . . . . . . . . . . 15 ⊢ (𝑧 ∈ {𝑥 ∣ ∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)} ↔ 𝑧 ∈ {𝑧 ∣ ∀𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧)})
66	64, 65	bitri 278	. . . . . . . . . . . . . 14 ⊢ ([𝑧 / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) ↔ 𝑧 ∈ {𝑧 ∣ ∀𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧)})
67		abid 2743	. . . . . . . . . . . . . 14 ⊢ (𝑧 ∈ {𝑧 ∣ ∀𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧)} ↔ ∀𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧))
68	66, 67	bitri 278	. . . . . . . . . . . . 13 ⊢ ([𝑧 / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) ↔ ∀𝑦 ∈ 𝑧 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑧))
69	63, 68	sylibr 237	. . . . . . . . . . . 12 ⊢ (Lim 𝑧 → [𝑧 / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥))
70	69	a1d 26	. . . . . . . . . . 11 ⊢ (Lim 𝑧 → (∀𝑥 ∈ 𝑧 ∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) → [𝑧 / 𝑥]∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)))
71	6, 55, 70	tfindes 7874	. . . . . . . . . 10 ⊢ (𝑥 ∈ On → ∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥))
72		rsp 3251	. . . . . . . . . 10 ⊢ (∀𝑦 ∈ 𝑥 (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) → (𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)))
73	71, 72	syl 18	. . . . . . . . 9 ⊢ (𝑥 ∈ On → (𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)))
74		eleq1 2849	. . . . . . . . . . 11 ⊢ (𝑥 = 𝑋 → (𝑥 ∈ On ↔ 𝑋 ∈ On))
75	74	adantl 487	. . . . . . . . . 10 ⊢ ((𝑦 = 𝑌 ∧ 𝑥 = 𝑋) → (𝑥 ∈ On ↔ 𝑋 ∈ On))
76		eleq12 2851	. . . . . . . . . . 11 ⊢ ((𝑦 = 𝑌 ∧ 𝑥 = 𝑋) → (𝑦 ∈ 𝑥 ↔ 𝑌 ∈ 𝑋))
77		fveq2 6885	. . . . . . . . . . . . 13 ⊢ (𝑦 = 𝑌 → (rec(𝐹, 𝐴)‘𝑦) = (rec(𝐹, 𝐴)‘𝑌))
78	77	adantr 486	. . . . . . . . . . . 12 ⊢ ((𝑦 = 𝑌 ∧ 𝑥 = 𝑋) → (rec(𝐹, 𝐴)‘𝑦) = (rec(𝐹, 𝐴)‘𝑌))
79		fveq2 6885	. . . . . . . . . . . . 13 ⊢ (𝑥 = 𝑋 → (rec(𝐹, 𝐴)‘𝑥) = (rec(𝐹, 𝐴)‘𝑋))
80	79	adantl 487	. . . . . . . . . . . 12 ⊢ ((𝑦 = 𝑌 ∧ 𝑥 = 𝑋) → (rec(𝐹, 𝐴)‘𝑥) = (rec(𝐹, 𝐴)‘𝑋))
81	78, 80	sseq12d 3964	. . . . . . . . . . 11 ⊢ ((𝑦 = 𝑌 ∧ 𝑥 = 𝑋) → ((rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥) ↔ (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋)))
82	76, 81	imbi12d 347	. . . . . . . . . 10 ⊢ ((𝑦 = 𝑌 ∧ 𝑥 = 𝑋) → ((𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥)) ↔ (𝑌 ∈ 𝑋 → (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋))))
83	75, 82	imbi12d 347	. . . . . . . . 9 ⊢ ((𝑦 = 𝑌 ∧ 𝑥 = 𝑋) → ((𝑥 ∈ On → (𝑦 ∈ 𝑥 → (rec(𝐹, 𝐴)‘𝑦) ⊆ (rec(𝐹, 𝐴)‘𝑥))) ↔ (𝑋 ∈ On → (𝑌 ∈ 𝑋 → (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋)))))
84	73, 83	mpbii 236	. . . . . . . 8 ⊢ ((𝑦 = 𝑌 ∧ 𝑥 = 𝑋) → (𝑋 ∈ On → (𝑌 ∈ 𝑋 → (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋))))
85	84	ex 418	. . . . . . 7 ⊢ (𝑦 = 𝑌 → (𝑥 = 𝑋 → (𝑋 ∈ On → (𝑌 ∈ 𝑋 → (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋)))))
86	85	vtocleg 3517	. . . . . 6 ⊢ (𝑌 ∈ 𝑋 → (𝑥 = 𝑋 → (𝑋 ∈ On → (𝑌 ∈ 𝑋 → (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋)))))
87	86	com12 33	. . . . 5 ⊢ (𝑥 = 𝑋 → (𝑌 ∈ 𝑋 → (𝑋 ∈ On → (𝑌 ∈ 𝑋 → (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋)))))
88	87	vtocleg 3517	. . . 4 ⊢ (𝑋 ∈ On → (𝑌 ∈ 𝑋 → (𝑋 ∈ On → (𝑌 ∈ 𝑋 → (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋)))))
89	88	pm2.43b 56	. . 3 ⊢ (𝑌 ∈ 𝑋 → (𝑋 ∈ On → (𝑌 ∈ 𝑋 → (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋))))
90	89	pm2.43b 56	. 2 ⊢ (𝑋 ∈ On → (𝑌 ∈ 𝑋 → (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋)))
91	90	imp 412	1 ⊢ ((𝑋 ∈ On ∧ 𝑌 ∈ 𝑋) → (rec(𝐹, 𝐴)‘𝑌) ⊆ (rec(𝐹, 𝐴)‘𝑋))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   ∨ wo 861   = wceq 1570   ∈ wcel 2145  {cab 2739  ∀wral 3077  Vcvv 3451  [wsbc 3739  ⦋csb 3847   ∪ cun 3897   ⊆ wss 3899  ∅c0 4279  ∪ ciun 4951   ↦ cmpt 5186  Oncon0 6362  Lim wlim 6363  suc csuc 6364  ‘cfv 6538  reccrdg 8417

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 2733  ax-rep 5232  ax-sep 5249  ax-nul 5260  ax-pr 5391  ax-un 7751

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 2565  df-eu 2595  df-clab 2740  df-cleq 2753  df-clel 2836  df-nfc 2910  df-ne 2957  df-ral 3078  df-rex 3088  df-reu 3367  df-rab 3414  df-v 3453  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-op 4591  df-uni 4868  df-iun 4953  df-br 5104  df-opab 5168  df-mpt 5187  df-tr 5213  df-id 5546  df-eprel 5551  df-po 5559  df-so 5560  df-fr 5604  df-we 5606  df-xp 5657  df-rel 5658  df-cnv 5659  df-co 5660  df-dm 5661  df-rn 5662  df-res 5663  df-ima 5664  df-pred 6304  df-ord 6365  df-on 6366  df-lim 6367  df-suc 6368  df-iota 6494  df-fun 6540  df-fn 6541  df-f 6542  df-f1 6543  df-fo 6544  df-f1o 6545  df-fv 6546  df-ov 7423  df-2nd 8002  df-frecs 8299  df-wrecs 8330  df-recs 8379  df-rdg 8418

This theorem is used by: (None)