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Theorem hashf1lem1 13096

Description: Lemma for hashf1 13098. (Contributed by Mario Carneiro, 17-Apr-2015.)

**Hypotheses**
Ref	Expression
hashf1lem2.1	⊢ (𝜑 → 𝐴 ∈ Fin)
hashf1lem2.2	⊢ (𝜑 → 𝐵 ∈ Fin)
hashf1lem2.3	⊢ (𝜑 → ¬ 𝑧 ∈ 𝐴)
hashf1lem2.4	⊢ (𝜑 → ((#‘𝐴) + 1) ≤ (#‘𝐵))
hashf1lem1.5	⊢ (𝜑 → 𝐹:𝐴–1-1→𝐵)

**Assertion**
Ref	Expression
hashf1lem1	⊢ (𝜑 → {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} ≈ (𝐵 ∖ ran 𝐹))

Distinct variable groups: 𝑧,𝑓 𝐴,𝑓 𝐵,𝑓 𝜑,𝑓 𝑓,𝐹 Allowed substitution hints: 𝜑(𝑧) 𝐴(𝑧) 𝐵(𝑧) 𝐹(𝑧)

Proof of Theorem hashf1lem1 Dummy variables 𝑔 𝑥 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		f1f 6014	. . . . . 6 ⊢ (𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵 → 𝑓:(𝐴 ∪ {𝑧})⟶𝐵)
2	1	adantl 481	. . . . 5 ⊢ (((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵) → 𝑓:(𝐴 ∪ {𝑧})⟶𝐵)
3		hashf1lem2.2	. . . . . 6 ⊢ (𝜑 → 𝐵 ∈ Fin)
4		hashf1lem2.1	. . . . . . 7 ⊢ (𝜑 → 𝐴 ∈ Fin)
5		snfi 7923	. . . . . . 7 ⊢ {𝑧} ∈ Fin
6		unfi 8112	. . . . . . 7 ⊢ ((𝐴 ∈ Fin ∧ {𝑧} ∈ Fin) → (𝐴 ∪ {𝑧}) ∈ Fin)
7	4, 5, 6	sylancl 693	. . . . . 6 ⊢ (𝜑 → (𝐴 ∪ {𝑧}) ∈ Fin)
8	3, 7	elmapd 7758	. . . . 5 ⊢ (𝜑 → (𝑓 ∈ (𝐵 ↑_𝑚 (𝐴 ∪ {𝑧})) ↔ 𝑓:(𝐴 ∪ {𝑧})⟶𝐵))
9	2, 8	syl5ibr 235	. . . 4 ⊢ (𝜑 → (((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵) → 𝑓 ∈ (𝐵 ↑_𝑚 (𝐴 ∪ {𝑧}))))
10	9	abssdv 3639	. . 3 ⊢ (𝜑 → {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} ⊆ (𝐵 ↑_𝑚 (𝐴 ∪ {𝑧})))
11		ovex 6577	. . 3 ⊢ (𝐵 ↑_𝑚 (𝐴 ∪ {𝑧})) ∈ V
12		ssexg 4732	. . 3 ⊢ (({𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} ⊆ (𝐵 ↑_𝑚 (𝐴 ∪ {𝑧})) ∧ (𝐵 ↑_𝑚 (𝐴 ∪ {𝑧})) ∈ V) → {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} ∈ V)
13	10, 11, 12	sylancl 693	. 2 ⊢ (𝜑 → {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} ∈ V)
14		difexg 4735	. . 3 ⊢ (𝐵 ∈ Fin → (𝐵 ∖ ran 𝐹) ∈ V)
15	3, 14	syl 17	. 2 ⊢ (𝜑 → (𝐵 ∖ ran 𝐹) ∈ V)
16		vex 3176	. . . 4 ⊢ 𝑔 ∈ V
17		reseq1 5311	. . . . . 6 ⊢ (𝑓 = 𝑔 → (𝑓 ↾ 𝐴) = (𝑔 ↾ 𝐴))
18	17	eqeq1d 2612	. . . . 5 ⊢ (𝑓 = 𝑔 → ((𝑓 ↾ 𝐴) = 𝐹 ↔ (𝑔 ↾ 𝐴) = 𝐹))
19		f1eq1 6009	. . . . 5 ⊢ (𝑓 = 𝑔 → (𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵 ↔ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵))
20	18, 19	anbi12d 743	. . . 4 ⊢ (𝑓 = 𝑔 → (((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵) ↔ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)))
21	16, 20	elab 3319	. . 3 ⊢ (𝑔 ∈ {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} ↔ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵))
22		f1f 6014	. . . . . . 7 ⊢ (𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵 → 𝑔:(𝐴 ∪ {𝑧})⟶𝐵)
23	22	ad2antll 761	. . . . . 6 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → 𝑔:(𝐴 ∪ {𝑧})⟶𝐵)
24		ssun2 3739	. . . . . . 7 ⊢ {𝑧} ⊆ (𝐴 ∪ {𝑧})
25		vex 3176	. . . . . . . 8 ⊢ 𝑧 ∈ V
26	25	snss 4259	. . . . . . 7 ⊢ (𝑧 ∈ (𝐴 ∪ {𝑧}) ↔ {𝑧} ⊆ (𝐴 ∪ {𝑧}))
27	24, 26	mpbir 220	. . . . . 6 ⊢ 𝑧 ∈ (𝐴 ∪ {𝑧})
28		ffvelrn 6265	. . . . . 6 ⊢ ((𝑔:(𝐴 ∪ {𝑧})⟶𝐵 ∧ 𝑧 ∈ (𝐴 ∪ {𝑧})) → (𝑔‘𝑧) ∈ 𝐵)
29	23, 27, 28	sylancl 693	. . . . 5 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → (𝑔‘𝑧) ∈ 𝐵)
30		hashf1lem2.3	. . . . . . 7 ⊢ (𝜑 → ¬ 𝑧 ∈ 𝐴)
31	30	adantr 480	. . . . . 6 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → ¬ 𝑧 ∈ 𝐴)
32		df-ima 5051	. . . . . . . . 9 ⊢ (𝑔 “ 𝐴) = ran (𝑔 ↾ 𝐴)
33		simprl 790	. . . . . . . . . 10 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → (𝑔 ↾ 𝐴) = 𝐹)
34	33	rneqd 5274	. . . . . . . . 9 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → ran (𝑔 ↾ 𝐴) = ran 𝐹)
35	32, 34	syl5eq 2656	. . . . . . . 8 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → (𝑔 “ 𝐴) = ran 𝐹)
36	35	eleq2d 2673	. . . . . . 7 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → ((𝑔‘𝑧) ∈ (𝑔 “ 𝐴) ↔ (𝑔‘𝑧) ∈ ran 𝐹))
37		simprr 792	. . . . . . . 8 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)
38	27	a1i 11	. . . . . . . 8 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → 𝑧 ∈ (𝐴 ∪ {𝑧}))
39		ssun1 3738	. . . . . . . . 9 ⊢ 𝐴 ⊆ (𝐴 ∪ {𝑧})
40	39	a1i 11	. . . . . . . 8 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → 𝐴 ⊆ (𝐴 ∪ {𝑧}))
41		f1elima 6421	. . . . . . . 8 ⊢ ((𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵 ∧ 𝑧 ∈ (𝐴 ∪ {𝑧}) ∧ 𝐴 ⊆ (𝐴 ∪ {𝑧})) → ((𝑔‘𝑧) ∈ (𝑔 “ 𝐴) ↔ 𝑧 ∈ 𝐴))
42	37, 38, 40, 41	syl3anc 1318	. . . . . . 7 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → ((𝑔‘𝑧) ∈ (𝑔 “ 𝐴) ↔ 𝑧 ∈ 𝐴))
43	36, 42	bitr3d 269	. . . . . 6 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → ((𝑔‘𝑧) ∈ ran 𝐹 ↔ 𝑧 ∈ 𝐴))
44	31, 43	mtbird 314	. . . . 5 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → ¬ (𝑔‘𝑧) ∈ ran 𝐹)
45	29, 44	eldifd 3551	. . . 4 ⊢ ((𝜑 ∧ ((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)) → (𝑔‘𝑧) ∈ (𝐵 ∖ ran 𝐹))
46	45	ex 449	. . 3 ⊢ (𝜑 → (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) → (𝑔‘𝑧) ∈ (𝐵 ∖ ran 𝐹)))
47	21, 46	syl5bi 231	. 2 ⊢ (𝜑 → (𝑔 ∈ {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} → (𝑔‘𝑧) ∈ (𝐵 ∖ ran 𝐹)))
48		hashf1lem1.5	. . . . . . 7 ⊢ (𝜑 → 𝐹:𝐴–1-1→𝐵)
49		f1f 6014	. . . . . . 7 ⊢ (𝐹:𝐴–1-1→𝐵 → 𝐹:𝐴⟶𝐵)
50	48, 49	syl 17	. . . . . 6 ⊢ (𝜑 → 𝐹:𝐴⟶𝐵)
51	50	adantr 480	. . . . 5 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → 𝐹:𝐴⟶𝐵)
52		vex 3176	. . . . . . . 8 ⊢ 𝑥 ∈ V
53	25, 52	f1osn 6088	. . . . . . 7 ⊢ {⟨𝑧, 𝑥⟩}:{𝑧}–1-1-onto→{𝑥}
54		f1of 6050	. . . . . . 7 ⊢ ({⟨𝑧, 𝑥⟩}:{𝑧}–1-1-onto→{𝑥} → {⟨𝑧, 𝑥⟩}:{𝑧}⟶{𝑥})
55	53, 54	ax-mp 5	. . . . . 6 ⊢ {⟨𝑧, 𝑥⟩}:{𝑧}⟶{𝑥}
56		eldifi 3694	. . . . . . . 8 ⊢ (𝑥 ∈ (𝐵 ∖ ran 𝐹) → 𝑥 ∈ 𝐵)
57	56	adantl 481	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → 𝑥 ∈ 𝐵)
58	57	snssd 4281	. . . . . 6 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → {𝑥} ⊆ 𝐵)
59		fss 5969	. . . . . 6 ⊢ (({⟨𝑧, 𝑥⟩}:{𝑧}⟶{𝑥} ∧ {𝑥} ⊆ 𝐵) → {⟨𝑧, 𝑥⟩}:{𝑧}⟶𝐵)
60	55, 58, 59	sylancr 694	. . . . 5 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → {⟨𝑧, 𝑥⟩}:{𝑧}⟶𝐵)
61		res0 5321	. . . . . . 7 ⊢ (𝐹 ↾ ∅) = ∅
62		res0 5321	. . . . . . 7 ⊢ ({⟨𝑧, 𝑥⟩} ↾ ∅) = ∅
63	61, 62	eqtr4i 2635	. . . . . 6 ⊢ (𝐹 ↾ ∅) = ({⟨𝑧, 𝑥⟩} ↾ ∅)
64		disjsn 4192	. . . . . . . . 9 ⊢ ((𝐴 ∩ {𝑧}) = ∅ ↔ ¬ 𝑧 ∈ 𝐴)
65	30, 64	sylibr 223	. . . . . . . 8 ⊢ (𝜑 → (𝐴 ∩ {𝑧}) = ∅)
66	65	adantr 480	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (𝐴 ∩ {𝑧}) = ∅)
67	66	reseq2d 5317	. . . . . 6 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (𝐹 ↾ (𝐴 ∩ {𝑧})) = (𝐹 ↾ ∅))
68	66	reseq2d 5317	. . . . . 6 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → ({⟨𝑧, 𝑥⟩} ↾ (𝐴 ∩ {𝑧})) = ({⟨𝑧, 𝑥⟩} ↾ ∅))
69	63, 67, 68	3eqtr4a 2670	. . . . 5 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (𝐹 ↾ (𝐴 ∩ {𝑧})) = ({⟨𝑧, 𝑥⟩} ↾ (𝐴 ∩ {𝑧})))
70		fresaunres1 5990	. . . . 5 ⊢ ((𝐹:𝐴⟶𝐵 ∧ {⟨𝑧, 𝑥⟩}:{𝑧}⟶𝐵 ∧ (𝐹 ↾ (𝐴 ∩ {𝑧})) = ({⟨𝑧, 𝑥⟩} ↾ (𝐴 ∩ {𝑧}))) → ((𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↾ 𝐴) = 𝐹)
71	51, 60, 69, 70	syl3anc 1318	. . . 4 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → ((𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↾ 𝐴) = 𝐹)
72		f1f1orn 6061	. . . . . . . . 9 ⊢ (𝐹:𝐴–1-1→𝐵 → 𝐹:𝐴–1-1-onto→ran 𝐹)
73	48, 72	syl 17	. . . . . . . 8 ⊢ (𝜑 → 𝐹:𝐴–1-1-onto→ran 𝐹)
74	73	adantr 480	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → 𝐹:𝐴–1-1-onto→ran 𝐹)
75	53	a1i 11	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → {⟨𝑧, 𝑥⟩}:{𝑧}–1-1-onto→{𝑥})
76		eldifn 3695	. . . . . . . . 9 ⊢ (𝑥 ∈ (𝐵 ∖ ran 𝐹) → ¬ 𝑥 ∈ ran 𝐹)
77	76	adantl 481	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → ¬ 𝑥 ∈ ran 𝐹)
78		disjsn 4192	. . . . . . . 8 ⊢ ((ran 𝐹 ∩ {𝑥}) = ∅ ↔ ¬ 𝑥 ∈ ran 𝐹)
79	77, 78	sylibr 223	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (ran 𝐹 ∩ {𝑥}) = ∅)
80		f1oun 6069	. . . . . . 7 ⊢ (((𝐹:𝐴–1-1-onto→ran 𝐹 ∧ {⟨𝑧, 𝑥⟩}:{𝑧}–1-1-onto→{𝑥}) ∧ ((𝐴 ∩ {𝑧}) = ∅ ∧ (ran 𝐹 ∩ {𝑥}) = ∅)) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1-onto→(ran 𝐹 ∪ {𝑥}))
81	74, 75, 66, 79, 80	syl22anc 1319	. . . . . 6 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1-onto→(ran 𝐹 ∪ {𝑥}))
82		f1of1 6049	. . . . . 6 ⊢ ((𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1-onto→(ran 𝐹 ∪ {𝑥}) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1→(ran 𝐹 ∪ {𝑥}))
83	81, 82	syl 17	. . . . 5 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1→(ran 𝐹 ∪ {𝑥}))
84		frn 5966	. . . . . . 7 ⊢ (𝐹:𝐴⟶𝐵 → ran 𝐹 ⊆ 𝐵)
85	51, 84	syl 17	. . . . . 6 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → ran 𝐹 ⊆ 𝐵)
86	85, 58	unssd 3751	. . . . 5 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (ran 𝐹 ∪ {𝑥}) ⊆ 𝐵)
87		f1ss 6019	. . . . 5 ⊢ (((𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1→(ran 𝐹 ∪ {𝑥}) ∧ (ran 𝐹 ∪ {𝑥}) ⊆ 𝐵) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1→𝐵)
88	83, 86, 87	syl2anc 691	. . . 4 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1→𝐵)
89		fex 6394	. . . . . . . 8 ⊢ ((𝐹:𝐴⟶𝐵 ∧ 𝐴 ∈ Fin) → 𝐹 ∈ V)
90	50, 4, 89	syl2anc 691	. . . . . . 7 ⊢ (𝜑 → 𝐹 ∈ V)
91	90	adantr 480	. . . . . 6 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → 𝐹 ∈ V)
92		snex 4835	. . . . . 6 ⊢ {⟨𝑧, 𝑥⟩} ∈ V
93		unexg 6857	. . . . . 6 ⊢ ((𝐹 ∈ V ∧ {⟨𝑧, 𝑥⟩} ∈ V) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}) ∈ V)
94	91, 92, 93	sylancl 693	. . . . 5 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}) ∈ V)
95		reseq1 5311	. . . . . . . 8 ⊢ (𝑓 = (𝐹 ∪ {⟨𝑧, 𝑥⟩}) → (𝑓 ↾ 𝐴) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↾ 𝐴))
96	95	eqeq1d 2612	. . . . . . 7 ⊢ (𝑓 = (𝐹 ∪ {⟨𝑧, 𝑥⟩}) → ((𝑓 ↾ 𝐴) = 𝐹 ↔ ((𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↾ 𝐴) = 𝐹))
97		f1eq1 6009	. . . . . . 7 ⊢ (𝑓 = (𝐹 ∪ {⟨𝑧, 𝑥⟩}) → (𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵 ↔ (𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1→𝐵))
98	96, 97	anbi12d 743	. . . . . 6 ⊢ (𝑓 = (𝐹 ∪ {⟨𝑧, 𝑥⟩}) → (((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵) ↔ (((𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↾ 𝐴) = 𝐹 ∧ (𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1→𝐵)))
99	98	elabg 3320	. . . . 5 ⊢ ((𝐹 ∪ {⟨𝑧, 𝑥⟩}) ∈ V → ((𝐹 ∪ {⟨𝑧, 𝑥⟩}) ∈ {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} ↔ (((𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↾ 𝐴) = 𝐹 ∧ (𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1→𝐵)))
100	94, 99	syl 17	. . . 4 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → ((𝐹 ∪ {⟨𝑧, 𝑥⟩}) ∈ {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} ↔ (((𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↾ 𝐴) = 𝐹 ∧ (𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1→𝐵)))
101	71, 88, 100	mpbir2and 959	. . 3 ⊢ ((𝜑 ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}) ∈ {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)})
102	101	ex 449	. 2 ⊢ (𝜑 → (𝑥 ∈ (𝐵 ∖ ran 𝐹) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}) ∈ {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)}))
103	21	anbi1i 727	. . 3 ⊢ ((𝑔 ∈ {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) ↔ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)))
104		simprlr 799	. . . . . . 7 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵)
105		f1fn 6015	. . . . . . 7 ⊢ (𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵 → 𝑔 Fn (𝐴 ∪ {𝑧}))
106	104, 105	syl 17	. . . . . 6 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → 𝑔 Fn (𝐴 ∪ {𝑧}))
107	81	adantrl 748	. . . . . . 7 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1-onto→(ran 𝐹 ∪ {𝑥}))
108		f1ofn 6051	. . . . . . 7 ⊢ ((𝐹 ∪ {⟨𝑧, 𝑥⟩}):(𝐴 ∪ {𝑧})–1-1-onto→(ran 𝐹 ∪ {𝑥}) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}) Fn (𝐴 ∪ {𝑧}))
109	107, 108	syl 17	. . . . . 6 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → (𝐹 ∪ {⟨𝑧, 𝑥⟩}) Fn (𝐴 ∪ {𝑧}))
110		eqfnfv 6219	. . . . . 6 ⊢ ((𝑔 Fn (𝐴 ∪ {𝑧}) ∧ (𝐹 ∪ {⟨𝑧, 𝑥⟩}) Fn (𝐴 ∪ {𝑧})) → (𝑔 = (𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↔ ∀𝑦 ∈ (𝐴 ∪ {𝑧})(𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦)))
111	106, 109, 110	syl2anc 691	. . . . 5 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → (𝑔 = (𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↔ ∀𝑦 ∈ (𝐴 ∪ {𝑧})(𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦)))
112		fvres 6117	. . . . . . . . . . 11 ⊢ (𝑦 ∈ 𝐴 → ((𝑔 ↾ 𝐴)‘𝑦) = (𝑔‘𝑦))
113	112	eqcomd 2616	. . . . . . . . . 10 ⊢ (𝑦 ∈ 𝐴 → (𝑔‘𝑦) = ((𝑔 ↾ 𝐴)‘𝑦))
114		simprll 798	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → (𝑔 ↾ 𝐴) = 𝐹)
115	114	fveq1d 6105	. . . . . . . . . 10 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → ((𝑔 ↾ 𝐴)‘𝑦) = (𝐹‘𝑦))
116	113, 115	sylan9eqr 2666	. . . . . . . . 9 ⊢ (((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) ∧ 𝑦 ∈ 𝐴) → (𝑔‘𝑦) = (𝐹‘𝑦))
117	48	ad2antrr 758	. . . . . . . . . . 11 ⊢ (((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) ∧ 𝑦 ∈ 𝐴) → 𝐹:𝐴–1-1→𝐵)
118		f1fn 6015	. . . . . . . . . . 11 ⊢ (𝐹:𝐴–1-1→𝐵 → 𝐹 Fn 𝐴)
119	117, 118	syl 17	. . . . . . . . . 10 ⊢ (((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) ∧ 𝑦 ∈ 𝐴) → 𝐹 Fn 𝐴)
120	25, 52	fnsn 5860	. . . . . . . . . . 11 ⊢ {⟨𝑧, 𝑥⟩} Fn {𝑧}
121	120	a1i 11	. . . . . . . . . 10 ⊢ (((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) ∧ 𝑦 ∈ 𝐴) → {⟨𝑧, 𝑥⟩} Fn {𝑧})
122	65	ad2antrr 758	. . . . . . . . . 10 ⊢ (((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) ∧ 𝑦 ∈ 𝐴) → (𝐴 ∩ {𝑧}) = ∅)
123		simpr 476	. . . . . . . . . 10 ⊢ (((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) ∧ 𝑦 ∈ 𝐴) → 𝑦 ∈ 𝐴)
124		fvun1 6179	. . . . . . . . . 10 ⊢ ((𝐹 Fn 𝐴 ∧ {⟨𝑧, 𝑥⟩} Fn {𝑧} ∧ ((𝐴 ∩ {𝑧}) = ∅ ∧ 𝑦 ∈ 𝐴)) → ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦) = (𝐹‘𝑦))
125	119, 121, 122, 123, 124	syl112anc 1322	. . . . . . . . 9 ⊢ (((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) ∧ 𝑦 ∈ 𝐴) → ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦) = (𝐹‘𝑦))
126	116, 125	eqtr4d 2647	. . . . . . . 8 ⊢ (((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) ∧ 𝑦 ∈ 𝐴) → (𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦))
127	126	ralrimiva 2949	. . . . . . 7 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → ∀𝑦 ∈ 𝐴 (𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦))
128	127	biantrurd 528	. . . . . 6 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → (∀𝑦 ∈ {𝑧} (𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦) ↔ (∀𝑦 ∈ 𝐴 (𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦) ∧ ∀𝑦 ∈ {𝑧} (𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦))))
129		ralunb 3756	. . . . . 6 ⊢ (∀𝑦 ∈ (𝐴 ∪ {𝑧})(𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦) ↔ (∀𝑦 ∈ 𝐴 (𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦) ∧ ∀𝑦 ∈ {𝑧} (𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦)))
130	128, 129	syl6bbr 277	. . . . 5 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → (∀𝑦 ∈ {𝑧} (𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦) ↔ ∀𝑦 ∈ (𝐴 ∪ {𝑧})(𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦)))
131	25	a1i 11	. . . . . . . 8 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → 𝑧 ∈ V)
132	52	a1i 11	. . . . . . . 8 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → 𝑥 ∈ V)
133		fdm 5964	. . . . . . . . . . . 12 ⊢ (𝐹:𝐴⟶𝐵 → dom 𝐹 = 𝐴)
134	50, 133	syl 17	. . . . . . . . . . 11 ⊢ (𝜑 → dom 𝐹 = 𝐴)
135	134	eleq2d 2673	. . . . . . . . . 10 ⊢ (𝜑 → (𝑧 ∈ dom 𝐹 ↔ 𝑧 ∈ 𝐴))
136	30, 135	mtbird 314	. . . . . . . . 9 ⊢ (𝜑 → ¬ 𝑧 ∈ dom 𝐹)
137	136	adantr 480	. . . . . . . 8 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → ¬ 𝑧 ∈ dom 𝐹)
138		fsnunfv 6358	. . . . . . . 8 ⊢ ((𝑧 ∈ V ∧ 𝑥 ∈ V ∧ ¬ 𝑧 ∈ dom 𝐹) → ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑧) = 𝑥)
139	131, 132, 137, 138	syl3anc 1318	. . . . . . 7 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑧) = 𝑥)
140	139	eqeq2d 2620	. . . . . 6 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → ((𝑔‘𝑧) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑧) ↔ (𝑔‘𝑧) = 𝑥))
141		fveq2 6103	. . . . . . . 8 ⊢ (𝑦 = 𝑧 → (𝑔‘𝑦) = (𝑔‘𝑧))
142		fveq2 6103	. . . . . . . 8 ⊢ (𝑦 = 𝑧 → ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑧))
143	141, 142	eqeq12d 2625	. . . . . . 7 ⊢ (𝑦 = 𝑧 → ((𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦) ↔ (𝑔‘𝑧) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑧)))
144	25, 143	ralsn 4169	. . . . . 6 ⊢ (∀𝑦 ∈ {𝑧} (𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦) ↔ (𝑔‘𝑧) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑧))
145		eqcom 2617	. . . . . 6 ⊢ (𝑥 = (𝑔‘𝑧) ↔ (𝑔‘𝑧) = 𝑥)
146	140, 144, 145	3bitr4g 302	. . . . 5 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → (∀𝑦 ∈ {𝑧} (𝑔‘𝑦) = ((𝐹 ∪ {⟨𝑧, 𝑥⟩})‘𝑦) ↔ 𝑥 = (𝑔‘𝑧)))
147	111, 130, 146	3bitr2d 295	. . . 4 ⊢ ((𝜑 ∧ (((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹))) → (𝑔 = (𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↔ 𝑥 = (𝑔‘𝑧)))
148	147	ex 449	. . 3 ⊢ (𝜑 → ((((𝑔 ↾ 𝐴) = 𝐹 ∧ 𝑔:(𝐴 ∪ {𝑧})–1-1→𝐵) ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (𝑔 = (𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↔ 𝑥 = (𝑔‘𝑧))))
149	103, 148	syl5bi 231	. 2 ⊢ (𝜑 → ((𝑔 ∈ {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} ∧ 𝑥 ∈ (𝐵 ∖ ran 𝐹)) → (𝑔 = (𝐹 ∪ {⟨𝑧, 𝑥⟩}) ↔ 𝑥 = (𝑔‘𝑧))))
150	13, 15, 47, 102, 149	en3d 7878	1 ⊢ (𝜑 → {𝑓 ∣ ((𝑓 ↾ 𝐴) = 𝐹 ∧ 𝑓:(𝐴 ∪ {𝑧})–1-1→𝐵)} ≈ (𝐵 ∖ ran 𝐹))

Colors of variables: wff setvar class

Syntax hints: ¬ wn 3 → wi 4 ↔ wb 195 ∧ wa 383 = wceq 1475 ∈ wcel 1977 {cab 2596 ∀wral 2896 Vcvv 3173 ∖ cdif 3537 ∪ cun 3538 ∩ cin 3539 ⊆ wss 3540 ∅c0 3874 {csn 4125 ⟨cop 4131 class class class wbr 4583 dom cdm 5038 ran crn 5039 ↾ cres 5040 “ cima 5041 Fn wfn 5799 ⟶wf 5800 –1-1→wf1 5801 –1-1-onto→wf1o 5803 ‘cfv 5804 (class class class)co 6549 ↑_𝑚 cmap 7744 ≈ cen 7838 Fincfn 7841 1c1 9816 + caddc 9818 ≤ cle 9954 #chash 12979

This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1713 ax-4 1728 ax-5 1827 ax-6 1875 ax-7 1922 ax-8 1979 ax-9 1986 ax-10 2006 ax-11 2021 ax-12 2034 ax-13 2234 ax-ext 2590 ax-rep 4699 ax-sep 4709 ax-nul 4717 ax-pow 4769 ax-pr 4833 ax-un 6847

This theorem depends on definitions: df-bi 196 df-or 384 df-an 385 df-3or 1032 df-3an 1033 df-tru 1478 df-ex 1696 df-nf 1701 df-sb 1868 df-eu 2462 df-mo 2463 df-clab 2597 df-cleq 2603 df-clel 2606 df-nfc 2740 df-ne 2782 df-ral 2901 df-rex 2902 df-reu 2903 df-rab 2905 df-v 3175 df-sbc 3403 df-csb 3500 df-dif 3543 df-un 3545 df-in 3547 df-ss 3554 df-pss 3556 df-nul 3875 df-if 4037 df-pw 4110 df-sn 4126 df-pr 4128 df-tp 4130 df-op 4132 df-uni 4373 df-int 4411 df-iun 4457 df-br 4584 df-opab 4644 df-mpt 4645 df-tr 4681 df-eprel 4949 df-id 4953 df-po 4959 df-so 4960 df-fr 4997 df-we 4999 df-xp 5044 df-rel 5045 df-cnv 5046 df-co 5047 df-dm 5048 df-rn 5049 df-res 5050 df-ima 5051 df-pred 5597 df-ord 5643 df-on 5644 df-lim 5645 df-suc 5646 df-iota 5768 df-fun 5806 df-fn 5807 df-f 5808 df-f1 5809 df-fo 5810 df-f1o 5811 df-fv 5812 df-ov 6552 df-oprab 6553 df-mpt2 6554 df-om 6958 df-wrecs 7294 df-recs 7355 df-rdg 7393 df-1o 7447 df-oadd 7451 df-er 7629 df-map 7746 df-en 7842 df-fin 7845

This theorem is referenced by: hashf1lem2 13097

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