Theorem fseq1p1m1 13546

Description: Add/remove an item to/from the end of a finite sequence. (Contributed by Paul Chapman, 17-Nov-2012.) (Revised by Mario Carneiro, 7-Mar-2014.)

Hypothesis

Ref	Expression
fseq1p1m1.1	⊢ 𝐻 = {⟨(𝑁 + 1), 𝐵⟩}

Assertion

Ref	Expression
fseq1p1m1	⊢ (𝑁 ∈ ℕ0 → ((𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻)) ↔ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))))

Proof of Theorem fseq1p1m1

Step	Hyp	Ref	Expression
1		simpr1 1196	. . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → 𝐹:(1...𝑁)⟶𝐴)
2		nn0p1nn 12470	. . . . . . . . 9 ⊢ (𝑁 ∈ ℕ0 → (𝑁 + 1) ∈ ℕ)
3	2	adantr 480	. . . . . . . 8 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝑁 + 1) ∈ ℕ)
4		simpr2 1197	. . . . . . . 8 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → 𝐵 ∈ 𝐴)
5		fseq1p1m1.1	. . . . . . . . 9 ⊢ 𝐻 = {⟨(𝑁 + 1), 𝐵⟩}
6		fsng 7085	. . . . . . . . 9 ⊢ (((𝑁 + 1) ∈ ℕ ∧ 𝐵 ∈ 𝐴) → (𝐻:{(𝑁 + 1)}⟶{𝐵} ↔ 𝐻 = {⟨(𝑁 + 1), 𝐵⟩}))
7	5, 6	mpbiri 258	. . . . . . . 8 ⊢ (((𝑁 + 1) ∈ ℕ ∧ 𝐵 ∈ 𝐴) → 𝐻:{(𝑁 + 1)}⟶{𝐵})
8	3, 4, 7	syl2anc 585	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → 𝐻:{(𝑁 + 1)}⟶{𝐵})
9	4	snssd 4753	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → {𝐵} ⊆ 𝐴)
10	8, 9	fssd 6680	. . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → 𝐻:{(𝑁 + 1)}⟶𝐴)
11		fzp1disj 13531	. . . . . . 7 ⊢ ((1...𝑁) ∩ {(𝑁 + 1)}) = ∅
12	11	a1i 11	. . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → ((1...𝑁) ∩ {(𝑁 + 1)}) = ∅)
13	1, 10, 12	fun2d 6699	. . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐹 ∪ 𝐻):((1...𝑁) ∪ {(𝑁 + 1)})⟶𝐴)
14		1z 12551	. . . . . . . 8 ⊢ 1 ∈ ℤ
15		simpl 482	. . . . . . . . 9 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → 𝑁 ∈ ℕ0)
16		nn0uz 12820	. . . . . . . . . 10 ⊢ ℕ0 = (ℤ≥‘0)
17		1m1e0 12247	. . . . . . . . . . 11 ⊢ (1 − 1) = 0
18	17	fveq2i 6838	. . . . . . . . . 10 ⊢ (ℤ≥‘(1 − 1)) = (ℤ≥‘0)
19	16, 18	eqtr4i 2763	. . . . . . . . 9 ⊢ ℕ0 = (ℤ≥‘(1 − 1))
20	15, 19	eleqtrdi 2847	. . . . . . . 8 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → 𝑁 ∈ (ℤ≥‘(1 − 1)))
21		fzsuc2 13530	. . . . . . . 8 ⊢ ((1 ∈ ℤ ∧ 𝑁 ∈ (ℤ≥‘(1 − 1))) → (1...(𝑁 + 1)) = ((1...𝑁) ∪ {(𝑁 + 1)}))
22	14, 20, 21	sylancr 588	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (1...(𝑁 + 1)) = ((1...𝑁) ∪ {(𝑁 + 1)}))
23	22	eqcomd 2743	. . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → ((1...𝑁) ∪ {(𝑁 + 1)}) = (1...(𝑁 + 1)))
24	23	feq2d 6647	. . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → ((𝐹 ∪ 𝐻):((1...𝑁) ∪ {(𝑁 + 1)})⟶𝐴 ↔ (𝐹 ∪ 𝐻):(1...(𝑁 + 1))⟶𝐴))
25	13, 24	mpbid 232	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐹 ∪ 𝐻):(1...(𝑁 + 1))⟶𝐴)
26		simpr3 1198	. . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → 𝐺 = (𝐹 ∪ 𝐻))
27	26	feq1d 6645	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐺:(1...(𝑁 + 1))⟶𝐴 ↔ (𝐹 ∪ 𝐻):(1...(𝑁 + 1))⟶𝐴))
28	25, 27	mpbird 257	. . 3 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → 𝐺:(1...(𝑁 + 1))⟶𝐴)
29		ovex 7394	. . . . . 6 ⊢ (𝑁 + 1) ∈ V
30	29	snid 4607	. . . . 5 ⊢ (𝑁 + 1) ∈ {(𝑁 + 1)}
31		fvres 6854	. . . . 5 ⊢ ((𝑁 + 1) ∈ {(𝑁 + 1)} → ((𝐺 ↾ {(𝑁 + 1)})‘(𝑁 + 1)) = (𝐺‘(𝑁 + 1)))
32	30, 31	ax-mp 5	. . . 4 ⊢ ((𝐺 ↾ {(𝑁 + 1)})‘(𝑁 + 1)) = (𝐺‘(𝑁 + 1))
33	26	reseq1d 5938	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐺 ↾ {(𝑁 + 1)}) = ((𝐹 ∪ 𝐻) ↾ {(𝑁 + 1)}))
34		ffn 6663	. . . . . . . . . . 11 ⊢ (𝐹:(1...𝑁)⟶𝐴 → 𝐹 Fn (1...𝑁))
35		fnresdisj 6613	. . . . . . . . . . 11 ⊢ (𝐹 Fn (1...𝑁) → (((1...𝑁) ∩ {(𝑁 + 1)}) = ∅ ↔ (𝐹 ↾ {(𝑁 + 1)}) = ∅))
36	1, 34, 35	3syl 18	. . . . . . . . . 10 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (((1...𝑁) ∩ {(𝑁 + 1)}) = ∅ ↔ (𝐹 ↾ {(𝑁 + 1)}) = ∅))
37	12, 36	mpbid 232	. . . . . . . . 9 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐹 ↾ {(𝑁 + 1)}) = ∅)
38	37	uneq1d 4108	. . . . . . . 8 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → ((𝐹 ↾ {(𝑁 + 1)}) ∪ (𝐻 ↾ {(𝑁 + 1)})) = (∅ ∪ (𝐻 ↾ {(𝑁 + 1)})))
39		resundir 5954	. . . . . . . 8 ⊢ ((𝐹 ∪ 𝐻) ↾ {(𝑁 + 1)}) = ((𝐹 ↾ {(𝑁 + 1)}) ∪ (𝐻 ↾ {(𝑁 + 1)}))
40		uncom 4099	. . . . . . . . 9 ⊢ (∅ ∪ (𝐻 ↾ {(𝑁 + 1)})) = ((𝐻 ↾ {(𝑁 + 1)}) ∪ ∅)
41		un0 4335	. . . . . . . . 9 ⊢ ((𝐻 ↾ {(𝑁 + 1)}) ∪ ∅) = (𝐻 ↾ {(𝑁 + 1)})
42	40, 41	eqtr2i 2761	. . . . . . . 8 ⊢ (𝐻 ↾ {(𝑁 + 1)}) = (∅ ∪ (𝐻 ↾ {(𝑁 + 1)}))
43	38, 39, 42	3eqtr4g 2797	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → ((𝐹 ∪ 𝐻) ↾ {(𝑁 + 1)}) = (𝐻 ↾ {(𝑁 + 1)}))
44		ffn 6663	. . . . . . . 8 ⊢ (𝐻:{(𝑁 + 1)}⟶𝐴 → 𝐻 Fn {(𝑁 + 1)})
45		fnresdm 6612	. . . . . . . 8 ⊢ (𝐻 Fn {(𝑁 + 1)} → (𝐻 ↾ {(𝑁 + 1)}) = 𝐻)
46	10, 44, 45	3syl 18	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐻 ↾ {(𝑁 + 1)}) = 𝐻)
47	33, 43, 46	3eqtrd 2776	. . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐺 ↾ {(𝑁 + 1)}) = 𝐻)
48	47	fveq1d 6837	. . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → ((𝐺 ↾ {(𝑁 + 1)})‘(𝑁 + 1)) = (𝐻‘(𝑁 + 1)))
49	5	fveq1i 6836	. . . . . . 7 ⊢ (𝐻‘(𝑁 + 1)) = ({⟨(𝑁 + 1), 𝐵⟩}‘(𝑁 + 1))
50		fvsng 7129	. . . . . . 7 ⊢ (((𝑁 + 1) ∈ ℕ ∧ 𝐵 ∈ 𝐴) → ({⟨(𝑁 + 1), 𝐵⟩}‘(𝑁 + 1)) = 𝐵)
51	49, 50	eqtrid 2784	. . . . . 6 ⊢ (((𝑁 + 1) ∈ ℕ ∧ 𝐵 ∈ 𝐴) → (𝐻‘(𝑁 + 1)) = 𝐵)
52	3, 4, 51	syl2anc 585	. . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐻‘(𝑁 + 1)) = 𝐵)
53	48, 52	eqtrd 2772	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → ((𝐺 ↾ {(𝑁 + 1)})‘(𝑁 + 1)) = 𝐵)
54	32, 53	eqtr3id 2786	. . 3 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐺‘(𝑁 + 1)) = 𝐵)
55	26	reseq1d 5938	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐺 ↾ (1...𝑁)) = ((𝐹 ∪ 𝐻) ↾ (1...𝑁)))
56		incom 4150	. . . . . . . 8 ⊢ ({(𝑁 + 1)} ∩ (1...𝑁)) = ((1...𝑁) ∩ {(𝑁 + 1)})
57	56, 12	eqtrid 2784	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → ({(𝑁 + 1)} ∩ (1...𝑁)) = ∅)
58		ffn 6663	. . . . . . . 8 ⊢ (𝐻:{(𝑁 + 1)}⟶{𝐵} → 𝐻 Fn {(𝑁 + 1)})
59		fnresdisj 6613	. . . . . . . 8 ⊢ (𝐻 Fn {(𝑁 + 1)} → (({(𝑁 + 1)} ∩ (1...𝑁)) = ∅ ↔ (𝐻 ↾ (1...𝑁)) = ∅))
60	8, 58, 59	3syl 18	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (({(𝑁 + 1)} ∩ (1...𝑁)) = ∅ ↔ (𝐻 ↾ (1...𝑁)) = ∅))
61	57, 60	mpbid 232	. . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐻 ↾ (1...𝑁)) = ∅)
62	61	uneq2d 4109	. . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → ((𝐹 ↾ (1...𝑁)) ∪ (𝐻 ↾ (1...𝑁))) = ((𝐹 ↾ (1...𝑁)) ∪ ∅))
63		resundir 5954	. . . . 5 ⊢ ((𝐹 ∪ 𝐻) ↾ (1...𝑁)) = ((𝐹 ↾ (1...𝑁)) ∪ (𝐻 ↾ (1...𝑁)))
64		un0 4335	. . . . . 6 ⊢ ((𝐹 ↾ (1...𝑁)) ∪ ∅) = (𝐹 ↾ (1...𝑁))
65	64	eqcomi 2746	. . . . 5 ⊢ (𝐹 ↾ (1...𝑁)) = ((𝐹 ↾ (1...𝑁)) ∪ ∅)
66	62, 63, 65	3eqtr4g 2797	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → ((𝐹 ∪ 𝐻) ↾ (1...𝑁)) = (𝐹 ↾ (1...𝑁)))
67		fnresdm 6612	. . . . 5 ⊢ (𝐹 Fn (1...𝑁) → (𝐹 ↾ (1...𝑁)) = 𝐹)
68	1, 34, 67	3syl 18	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐹 ↾ (1...𝑁)) = 𝐹)
69	55, 66, 68	3eqtrrd 2777	. . 3 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → 𝐹 = (𝐺 ↾ (1...𝑁)))
70	28, 54, 69	3jca 1129	. 2 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻))) → (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁))))
71		simpr1 1196	. . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → 𝐺:(1...(𝑁 + 1))⟶𝐴)
72		fzssp1 13515	. . . . 5 ⊢ (1...𝑁) ⊆ (1...(𝑁 + 1))
73		fssres 6701	. . . . 5 ⊢ ((𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (1...𝑁) ⊆ (1...(𝑁 + 1))) → (𝐺 ↾ (1...𝑁)):(1...𝑁)⟶𝐴)
74	71, 72, 73	sylancl 587	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝐺 ↾ (1...𝑁)):(1...𝑁)⟶𝐴)
75		simpr3 1198	. . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → 𝐹 = (𝐺 ↾ (1...𝑁)))
76	75	feq1d 6645	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝐹:(1...𝑁)⟶𝐴 ↔ (𝐺 ↾ (1...𝑁)):(1...𝑁)⟶𝐴))
77	74, 76	mpbird 257	. . 3 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → 𝐹:(1...𝑁)⟶𝐴)
78		simpr2 1197	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝐺‘(𝑁 + 1)) = 𝐵)
79	2	adantr 480	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝑁 + 1) ∈ ℕ)
80		nnuz 12821	. . . . . . 7 ⊢ ℕ = (ℤ≥‘1)
81	79, 80	eleqtrdi 2847	. . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝑁 + 1) ∈ (ℤ≥‘1))
82		eluzfz2 13480	. . . . . 6 ⊢ ((𝑁 + 1) ∈ (ℤ≥‘1) → (𝑁 + 1) ∈ (1...(𝑁 + 1)))
83	81, 82	syl 17	. . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝑁 + 1) ∈ (1...(𝑁 + 1)))
84	71, 83	ffvelcdmd 7032	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝐺‘(𝑁 + 1)) ∈ 𝐴)
85	78, 84	eqeltrrd 2838	. . 3 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → 𝐵 ∈ 𝐴)
86		ffn 6663	. . . . . . . . 9 ⊢ (𝐺:(1...(𝑁 + 1))⟶𝐴 → 𝐺 Fn (1...(𝑁 + 1)))
87	71, 86	syl 17	. . . . . . . 8 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → 𝐺 Fn (1...(𝑁 + 1)))
88		fnressn 7106	. . . . . . . 8 ⊢ ((𝐺 Fn (1...(𝑁 + 1)) ∧ (𝑁 + 1) ∈ (1...(𝑁 + 1))) → (𝐺 ↾ {(𝑁 + 1)}) = {⟨(𝑁 + 1), (𝐺‘(𝑁 + 1))⟩})
89	87, 83, 88	syl2anc 585	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝐺 ↾ {(𝑁 + 1)}) = {⟨(𝑁 + 1), (𝐺‘(𝑁 + 1))⟩})
90		opeq2 4818	. . . . . . . . 9 ⊢ ((𝐺‘(𝑁 + 1)) = 𝐵 → ⟨(𝑁 + 1), (𝐺‘(𝑁 + 1))⟩ = ⟨(𝑁 + 1), 𝐵⟩)
91	90	sneqd 4580	. . . . . . . 8 ⊢ ((𝐺‘(𝑁 + 1)) = 𝐵 → {⟨(𝑁 + 1), (𝐺‘(𝑁 + 1))⟩} = {⟨(𝑁 + 1), 𝐵⟩})
92	78, 91	syl 17	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → {⟨(𝑁 + 1), (𝐺‘(𝑁 + 1))⟩} = {⟨(𝑁 + 1), 𝐵⟩})
93	89, 92	eqtrd 2772	. . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝐺 ↾ {(𝑁 + 1)}) = {⟨(𝑁 + 1), 𝐵⟩})
94	5, 93	eqtr4id 2791	. . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → 𝐻 = (𝐺 ↾ {(𝑁 + 1)}))
95	75, 94	uneq12d 4110	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝐹 ∪ 𝐻) = ((𝐺 ↾ (1...𝑁)) ∪ (𝐺 ↾ {(𝑁 + 1)})))
96		simpl 482	. . . . . . . 8 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → 𝑁 ∈ ℕ0)
97	96, 19	eleqtrdi 2847	. . . . . . 7 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → 𝑁 ∈ (ℤ≥‘(1 − 1)))
98	14, 97, 21	sylancr 588	. . . . . 6 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (1...(𝑁 + 1)) = ((1...𝑁) ∪ {(𝑁 + 1)}))
99	98	reseq2d 5939	. . . . 5 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝐺 ↾ (1...(𝑁 + 1))) = (𝐺 ↾ ((1...𝑁) ∪ {(𝑁 + 1)})))
100		resundi 5953	. . . . 5 ⊢ (𝐺 ↾ ((1...𝑁) ∪ {(𝑁 + 1)})) = ((𝐺 ↾ (1...𝑁)) ∪ (𝐺 ↾ {(𝑁 + 1)}))
101	99, 100	eqtr2di 2789	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → ((𝐺 ↾ (1...𝑁)) ∪ (𝐺 ↾ {(𝑁 + 1)})) = (𝐺 ↾ (1...(𝑁 + 1))))
102		fnresdm 6612	. . . . 5 ⊢ (𝐺 Fn (1...(𝑁 + 1)) → (𝐺 ↾ (1...(𝑁 + 1))) = 𝐺)
103	71, 86, 102	3syl 18	. . . 4 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝐺 ↾ (1...(𝑁 + 1))) = 𝐺)
104	95, 101, 103	3eqtrrd 2777	. . 3 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → 𝐺 = (𝐹 ∪ 𝐻))
105	77, 85, 104	3jca 1129	. 2 ⊢ ((𝑁 ∈ ℕ0 ∧ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))) → (𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻)))
106	70, 105	impbida 801	1 ⊢ (𝑁 ∈ ℕ0 → ((𝐹:(1...𝑁)⟶𝐴 ∧ 𝐵 ∈ 𝐴 ∧ 𝐺 = (𝐹 ∪ 𝐻)) ↔ (𝐺:(1...(𝑁 + 1))⟶𝐴 ∧ (𝐺‘(𝑁 + 1)) = 𝐵 ∧ 𝐹 = (𝐺 ↾ (1...𝑁)))))

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   ∧ w3a 1087   = wceq 1542   ∈ wcel 2114   ∪ cun 3888   ∩ cin 3889   ⊆ wss 3890  ∅c0 4274  {csn 4568  ⟨cop 4574   ↾ cres 5627   Fn wfn 6488  ⟶wf 6489  ‘cfv 6493  (class class class)co 7361  0cc0 11032  1c1 11033   + caddc 11035   − cmin 11371  ℕcn 12168  ℕ₀cn0 12431  ℤcz 12518  ℤ_≥cuz 12782  ...cfz 13455

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1797  ax-4 1811  ax-5 1912  ax-6 1969  ax-7 2010  ax-8 2116  ax-9 2124  ax-10 2147  ax-11 2163  ax-12 2185  ax-ext 2709  ax-sep 5232  ax-nul 5242  ax-pow 5303  ax-pr 5371  ax-un 7683  ax-cnex 11088  ax-resscn 11089  ax-1cn 11090  ax-icn 11091  ax-addcl 11092  ax-addrcl 11093  ax-mulcl 11094  ax-mulrcl 11095  ax-mulcom 11096  ax-addass 11097  ax-mulass 11098  ax-distr 11099  ax-i2m1 11100  ax-1ne0 11101  ax-1rid 11102  ax-rnegex 11103  ax-rrecex 11104  ax-cnre 11105  ax-pre-lttri 11106  ax-pre-lttrn 11107  ax-pre-ltadd 11108  ax-pre-mulgt0 11109

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3or 1088  df-3an 1089  df-tru 1545  df-fal 1555  df-ex 1782  df-nf 1786  df-sb 2069  df-mo 2540  df-eu 2570  df-clab 2716  df-cleq 2729  df-clel 2812  df-nfc 2886  df-ne 2934  df-nel 3038  df-ral 3053  df-rex 3063  df-reu 3344  df-rab 3391  df-v 3432  df-sbc 3730  df-csb 3839  df-dif 3893  df-un 3895  df-in 3897  df-ss 3907  df-pss 3910  df-nul 4275  df-if 4468  df-pw 4544  df-sn 4569  df-pr 4571  df-op 4575  df-uni 4852  df-iun 4936  df-br 5087  df-opab 5149  df-mpt 5168  df-tr 5194  df-id 5520  df-eprel 5525  df-po 5533  df-so 5534  df-fr 5578  df-we 5580  df-xp 5631  df-rel 5632  df-cnv 5633  df-co 5634  df-dm 5635  df-rn 5636  df-res 5637  df-ima 5638  df-pred 6260  df-ord 6321  df-on 6322  df-lim 6323  df-suc 6324  df-iota 6449  df-fun 6495  df-fn 6496  df-f 6497  df-f1 6498  df-fo 6499  df-f1o 6500  df-fv 6501  df-riota 7318  df-ov 7364  df-oprab 7365  df-mpo 7366  df-om 7812  df-1st 7936  df-2nd 7937  df-frecs 8225  df-wrecs 8256  df-recs 8305  df-rdg 8343  df-er 8637  df-en 8888  df-dom 8889  df-sdom 8890  df-pnf 11175  df-mnf 11176  df-xr 11177  df-ltxr 11178  df-le 11179  df-sub 11373  df-neg 11374  df-nn 12169  df-n0 12432  df-z 12519  df-uz 12783  df-fz 13456

This theorem is referenced by:  fseq1m1p1  13547