stoweidlem11 - Mathbox for Glauco Siliprandi

	Mathbox for Glauco Siliprandi		< Previous Next > Nearby theorems
Mirrors > Home > MPE Home > Th. List > Mathboxes > stoweidlem11		Structured version Visualization version GIF version

Theorem stoweidlem11 41860

Description: This lemma is used to prove that there is a function 𝑔 as in the proof of [BrosowskiDeutsh] p. 92 (at the top of page 92): this lemma proves that g(t) < ( j + 1 / 3 ) * ε. Here 𝐸 is used to represent ε in the paper. (Contributed by Glauco Siliprandi, 20-Apr-2017.)

**Hypotheses**
Ref	Expression
stoweidlem11.1	⊢ (𝜑 → 𝑁 ∈ ℕ)
stoweidlem11.2	⊢ (𝜑 → 𝑡 ∈ 𝑇)
stoweidlem11.3	⊢ (𝜑 → 𝑗 ∈ (1...𝑁))
stoweidlem11.4	⊢ ((𝜑 ∧ 𝑖 ∈ (0...𝑁)) → (𝑋‘𝑖):𝑇⟶ℝ)
stoweidlem11.5	⊢ ((𝜑 ∧ 𝑖 ∈ (0...𝑁)) → ((𝑋‘𝑖)‘𝑡) ≤ 1)
stoweidlem11.6	⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → ((𝑋‘𝑖)‘𝑡) < (𝐸 / 𝑁))
stoweidlem11.7	⊢ (𝜑 → 𝐸 ∈ ℝ⁺)
stoweidlem11.8	⊢ (𝜑 → 𝐸 < (1 / 3))

**Assertion**
Ref	Expression
stoweidlem11	⊢ (𝜑 → ((𝑡 ∈ 𝑇 ↦ Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)))‘𝑡) < ((𝑗 + (1 / 3)) · 𝐸))

Distinct variable groups: 𝑖,𝑗 𝑡,𝑖,𝐸 𝑖,𝑁,𝑡 𝜑,𝑖 𝑡,𝑇 𝑡,𝑋 Allowed substitution hints: 𝜑(𝑡,𝑗) 𝑇(𝑖,𝑗) 𝐸(𝑗) 𝑁(𝑗) 𝑋(𝑖,𝑗)

**Proof of Theorem stoweidlem11**
Step	Hyp	Ref	Expression
1		stoweidlem11.2	. . 3 ⊢ (𝜑 → 𝑡 ∈ 𝑇)
2		sumex 14882	. . 3 ⊢ Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)) ∈ V
3		eqid 2797	. . . 4 ⊢ (𝑡 ∈ 𝑇 ↦ Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡))) = (𝑡 ∈ 𝑇 ↦ Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)))
4	3	fvmpt2 6652	. . 3 ⊢ ((𝑡 ∈ 𝑇 ∧ Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)) ∈ V) → ((𝑡 ∈ 𝑇 ↦ Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)))‘𝑡) = Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)))
5	1, 2, 4	sylancl 586	. 2 ⊢ (𝜑 → ((𝑡 ∈ 𝑇 ↦ Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)))‘𝑡) = Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)))
6		fzfid 13195	. . . 4 ⊢ (𝜑 → (0...𝑁) ∈ Fin)
7		stoweidlem11.7	. . . . . . 7 ⊢ (𝜑 → 𝐸 ∈ ℝ⁺)
8	7	rpred 12285	. . . . . 6 ⊢ (𝜑 → 𝐸 ∈ ℝ)
9	8	adantr 481	. . . . 5 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...𝑁)) → 𝐸 ∈ ℝ)
10		stoweidlem11.4	. . . . . 6 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...𝑁)) → (𝑋‘𝑖):𝑇⟶ℝ)
11	1	adantr 481	. . . . . 6 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...𝑁)) → 𝑡 ∈ 𝑇)
12	10, 11	ffvelrnd 6724	. . . . 5 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...𝑁)) → ((𝑋‘𝑖)‘𝑡) ∈ ℝ)
13	9, 12	remulcld 10524	. . . 4 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...𝑁)) → (𝐸 · ((𝑋‘𝑖)‘𝑡)) ∈ ℝ)
14	6, 13	fsumrecl 14928	. . 3 ⊢ (𝜑 → Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)) ∈ ℝ)
15		stoweidlem11.3	. . . . . . . . 9 ⊢ (𝜑 → 𝑗 ∈ (1...𝑁))
16		elfzuz 12758	. . . . . . . . 9 ⊢ (𝑗 ∈ (1...𝑁) → 𝑗 ∈ (ℤ_≥‘1))
17	15, 16	syl 17	. . . . . . . 8 ⊢ (𝜑 → 𝑗 ∈ (ℤ_≥‘1))
18		eluz2 12103	. . . . . . . 8 ⊢ (𝑗 ∈ (ℤ_≥‘1) ↔ (1 ∈ ℤ ∧ 𝑗 ∈ ℤ ∧ 1 ≤ 𝑗))
19	17, 18	sylib 219	. . . . . . 7 ⊢ (𝜑 → (1 ∈ ℤ ∧ 𝑗 ∈ ℤ ∧ 1 ≤ 𝑗))
20	19	simp2d 1136	. . . . . 6 ⊢ (𝜑 → 𝑗 ∈ ℤ)
21	20	zred 11941	. . . . 5 ⊢ (𝜑 → 𝑗 ∈ ℝ)
22	8, 21	remulcld 10524	. . . 4 ⊢ (𝜑 → (𝐸 · 𝑗) ∈ ℝ)
23		stoweidlem11.1	. . . . . . . 8 ⊢ (𝜑 → 𝑁 ∈ ℕ)
24	23	nnred 11507	. . . . . . 7 ⊢ (𝜑 → 𝑁 ∈ ℝ)
25	24, 21	resubcld 10922	. . . . . 6 ⊢ (𝜑 → (𝑁 − 𝑗) ∈ ℝ)
26		1red 10495	. . . . . 6 ⊢ (𝜑 → 1 ∈ ℝ)
27	25, 26	readdcld 10523	. . . . 5 ⊢ (𝜑 → ((𝑁 − 𝑗) + 1) ∈ ℝ)
28	8, 23	nndivred 11545	. . . . . 6 ⊢ (𝜑 → (𝐸 / 𝑁) ∈ ℝ)
29	8, 28	remulcld 10524	. . . . 5 ⊢ (𝜑 → (𝐸 · (𝐸 / 𝑁)) ∈ ℝ)
30	27, 29	remulcld 10524	. . . 4 ⊢ (𝜑 → (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁))) ∈ ℝ)
31	22, 30	readdcld 10523	. . 3 ⊢ (𝜑 → ((𝐸 · 𝑗) + (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁)))) ∈ ℝ)
32		3re 11571	. . . . . . 7 ⊢ 3 ∈ ℝ
33	32	a1i 11	. . . . . 6 ⊢ (𝜑 → 3 ∈ ℝ)
34		3ne0 11597	. . . . . . 7 ⊢ 3 ≠ 0
35	34	a1i 11	. . . . . 6 ⊢ (𝜑 → 3 ≠ 0)
36	33, 35	rereccld 11321	. . . . 5 ⊢ (𝜑 → (1 / 3) ∈ ℝ)
37	21, 36	readdcld 10523	. . . 4 ⊢ (𝜑 → (𝑗 + (1 / 3)) ∈ ℝ)
38	37, 8	remulcld 10524	. . 3 ⊢ (𝜑 → ((𝑗 + (1 / 3)) · 𝐸) ∈ ℝ)
39		fzfid 13195	. . . . . 6 ⊢ (𝜑 → (0...(𝑗 − 1)) ∈ Fin)
40	8	adantr 481	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...(𝑗 − 1))) → 𝐸 ∈ ℝ)
41		elfzelz 12762	. . . . . . . . . . . 12 ⊢ (𝑗 ∈ (1...𝑁) → 𝑗 ∈ ℤ)
42		peano2zm 11879	. . . . . . . . . . . 12 ⊢ (𝑗 ∈ ℤ → (𝑗 − 1) ∈ ℤ)
43	15, 41, 42	3syl 18	. . . . . . . . . . 11 ⊢ (𝜑 → (𝑗 − 1) ∈ ℤ)
44	23	nnzd 11940	. . . . . . . . . . 11 ⊢ (𝜑 → 𝑁 ∈ ℤ)
45	21, 26	resubcld 10922	. . . . . . . . . . . 12 ⊢ (𝜑 → (𝑗 − 1) ∈ ℝ)
46	21	lem1d 11427	. . . . . . . . . . . 12 ⊢ (𝜑 → (𝑗 − 1) ≤ 𝑗)
47		elfzuz3 12759	. . . . . . . . . . . . 13 ⊢ (𝑗 ∈ (1...𝑁) → 𝑁 ∈ (ℤ_≥‘𝑗))
48		eluzle 12110	. . . . . . . . . . . . 13 ⊢ (𝑁 ∈ (ℤ_≥‘𝑗) → 𝑗 ≤ 𝑁)
49	15, 47, 48	3syl 18	. . . . . . . . . . . 12 ⊢ (𝜑 → 𝑗 ≤ 𝑁)
50	45, 21, 24, 46, 49	letrd 10650	. . . . . . . . . . 11 ⊢ (𝜑 → (𝑗 − 1) ≤ 𝑁)
51		eluz2 12103	. . . . . . . . . . 11 ⊢ (𝑁 ∈ (ℤ_≥‘(𝑗 − 1)) ↔ ((𝑗 − 1) ∈ ℤ ∧ 𝑁 ∈ ℤ ∧ (𝑗 − 1) ≤ 𝑁))
52	43, 44, 50, 51	syl3anbrc 1336	. . . . . . . . . 10 ⊢ (𝜑 → 𝑁 ∈ (ℤ_≥‘(𝑗 − 1)))
53		fzss2 12801	. . . . . . . . . 10 ⊢ (𝑁 ∈ (ℤ_≥‘(𝑗 − 1)) → (0...(𝑗 − 1)) ⊆ (0...𝑁))
54	52, 53	syl 17	. . . . . . . . 9 ⊢ (𝜑 → (0...(𝑗 − 1)) ⊆ (0...𝑁))
55	54	sselda 3895	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...(𝑗 − 1))) → 𝑖 ∈ (0...𝑁))
56	55, 12	syldan 591	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...(𝑗 − 1))) → ((𝑋‘𝑖)‘𝑡) ∈ ℝ)
57	40, 56	remulcld 10524	. . . . . 6 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...(𝑗 − 1))) → (𝐸 · ((𝑋‘𝑖)‘𝑡)) ∈ ℝ)
58	39, 57	fsumrecl 14928	. . . . 5 ⊢ (𝜑 → Σ𝑖 ∈ (0...(𝑗 − 1))(𝐸 · ((𝑋‘𝑖)‘𝑡)) ∈ ℝ)
59	58, 30	readdcld 10523	. . . 4 ⊢ (𝜑 → (Σ𝑖 ∈ (0...(𝑗 − 1))(𝐸 · ((𝑋‘𝑖)‘𝑡)) + (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁)))) ∈ ℝ)
60	21	ltm1d 11426	. . . . . . 7 ⊢ (𝜑 → (𝑗 − 1) < 𝑗)
61		fzdisj 12788	. . . . . . 7 ⊢ ((𝑗 − 1) < 𝑗 → ((0...(𝑗 − 1)) ∩ (𝑗...𝑁)) = ∅)
62	60, 61	syl 17	. . . . . 6 ⊢ (𝜑 → ((0...(𝑗 − 1)) ∩ (𝑗...𝑁)) = ∅)
63		fzssp1 12804	. . . . . . . . . 10 ⊢ (0...(𝑁 − 1)) ⊆ (0...((𝑁 − 1) + 1))
64	23	nncnd 11508	. . . . . . . . . . . 12 ⊢ (𝜑 → 𝑁 ∈ ℂ)
65		1cnd 10489	. . . . . . . . . . . 12 ⊢ (𝜑 → 1 ∈ ℂ)
66	64, 65	npcand 10855	. . . . . . . . . . 11 ⊢ (𝜑 → ((𝑁 − 1) + 1) = 𝑁)
67	66	oveq2d 7039	. . . . . . . . . 10 ⊢ (𝜑 → (0...((𝑁 − 1) + 1)) = (0...𝑁))
68	63, 67	sseqtrid 3946	. . . . . . . . 9 ⊢ (𝜑 → (0...(𝑁 − 1)) ⊆ (0...𝑁))
69		1zzd 11867	. . . . . . . . . . . 12 ⊢ (𝜑 → 1 ∈ ℤ)
70		fzsubel 12797	. . . . . . . . . . . 12 ⊢ (((1 ∈ ℤ ∧ 𝑁 ∈ ℤ) ∧ (𝑗 ∈ ℤ ∧ 1 ∈ ℤ)) → (𝑗 ∈ (1...𝑁) ↔ (𝑗 − 1) ∈ ((1 − 1)...(𝑁 − 1))))
71	69, 44, 20, 69, 70	syl22anc 835	. . . . . . . . . . 11 ⊢ (𝜑 → (𝑗 ∈ (1...𝑁) ↔ (𝑗 − 1) ∈ ((1 − 1)...(𝑁 − 1))))
72	15, 71	mpbid 233	. . . . . . . . . 10 ⊢ (𝜑 → (𝑗 − 1) ∈ ((1 − 1)...(𝑁 − 1)))
73		1m1e0 11563	. . . . . . . . . . 11 ⊢ (1 − 1) = 0
74	73	oveq1i 7033	. . . . . . . . . 10 ⊢ ((1 − 1)...(𝑁 − 1)) = (0...(𝑁 − 1))
75	72, 74	syl6eleq 2895	. . . . . . . . 9 ⊢ (𝜑 → (𝑗 − 1) ∈ (0...(𝑁 − 1)))
76	68, 75	sseldd 3896	. . . . . . . 8 ⊢ (𝜑 → (𝑗 − 1) ∈ (0...𝑁))
77		fzsplit 12787	. . . . . . . 8 ⊢ ((𝑗 − 1) ∈ (0...𝑁) → (0...𝑁) = ((0...(𝑗 − 1)) ∪ (((𝑗 − 1) + 1)...𝑁)))
78	76, 77	syl 17	. . . . . . 7 ⊢ (𝜑 → (0...𝑁) = ((0...(𝑗 − 1)) ∪ (((𝑗 − 1) + 1)...𝑁)))
79	20	zcnd 11942	. . . . . . . . . 10 ⊢ (𝜑 → 𝑗 ∈ ℂ)
80	79, 65	npcand 10855	. . . . . . . . 9 ⊢ (𝜑 → ((𝑗 − 1) + 1) = 𝑗)
81	80	oveq1d 7038	. . . . . . . 8 ⊢ (𝜑 → (((𝑗 − 1) + 1)...𝑁) = (𝑗...𝑁))
82	81	uneq2d 4066	. . . . . . 7 ⊢ (𝜑 → ((0...(𝑗 − 1)) ∪ (((𝑗 − 1) + 1)...𝑁)) = ((0...(𝑗 − 1)) ∪ (𝑗...𝑁)))
83	78, 82	eqtrd 2833	. . . . . 6 ⊢ (𝜑 → (0...𝑁) = ((0...(𝑗 − 1)) ∪ (𝑗...𝑁)))
84	7	rpcnd 12287	. . . . . . . 8 ⊢ (𝜑 → 𝐸 ∈ ℂ)
85	84	adantr 481	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...𝑁)) → 𝐸 ∈ ℂ)
86	12	recnd 10522	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...𝑁)) → ((𝑋‘𝑖)‘𝑡) ∈ ℂ)
87	85, 86	mulcld 10514	. . . . . 6 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...𝑁)) → (𝐸 · ((𝑋‘𝑖)‘𝑡)) ∈ ℂ)
88	62, 83, 6, 87	fsumsplit 14934	. . . . 5 ⊢ (𝜑 → Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)) = (Σ𝑖 ∈ (0...(𝑗 − 1))(𝐸 · ((𝑋‘𝑖)‘𝑡)) + Σ𝑖 ∈ (𝑗...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡))))
89		fzfid 13195	. . . . . . 7 ⊢ (𝜑 → (𝑗...𝑁) ∈ Fin)
90	8	adantr 481	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → 𝐸 ∈ ℝ)
91		0zd 11847	. . . . . . . . . . . . 13 ⊢ (𝜑 → 0 ∈ ℤ)
92		0red 10497	. . . . . . . . . . . . . 14 ⊢ (𝜑 → 0 ∈ ℝ)
93		0le1 11017	. . . . . . . . . . . . . . 15 ⊢ 0 ≤ 1
94	93	a1i 11	. . . . . . . . . . . . . 14 ⊢ (𝜑 → 0 ≤ 1)
95	19	simp3d 1137	. . . . . . . . . . . . . 14 ⊢ (𝜑 → 1 ≤ 𝑗)
96	92, 26, 21, 94, 95	letrd 10650	. . . . . . . . . . . . 13 ⊢ (𝜑 → 0 ≤ 𝑗)
97		eluz2 12103	. . . . . . . . . . . . 13 ⊢ (𝑗 ∈ (ℤ_≥‘0) ↔ (0 ∈ ℤ ∧ 𝑗 ∈ ℤ ∧ 0 ≤ 𝑗))
98	91, 20, 96, 97	syl3anbrc 1336	. . . . . . . . . . . 12 ⊢ (𝜑 → 𝑗 ∈ (ℤ_≥‘0))
99		fzss1 12800	. . . . . . . . . . . 12 ⊢ (𝑗 ∈ (ℤ_≥‘0) → (𝑗...𝑁) ⊆ (0...𝑁))
100	98, 99	syl 17	. . . . . . . . . . 11 ⊢ (𝜑 → (𝑗...𝑁) ⊆ (0...𝑁))
101	100	sselda 3895	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → 𝑖 ∈ (0...𝑁))
102	101, 10	syldan 591	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → (𝑋‘𝑖):𝑇⟶ℝ)
103	1	adantr 481	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → 𝑡 ∈ 𝑇)
104	102, 103	ffvelrnd 6724	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → ((𝑋‘𝑖)‘𝑡) ∈ ℝ)
105	90, 104	remulcld 10524	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → (𝐸 · ((𝑋‘𝑖)‘𝑡)) ∈ ℝ)
106	89, 105	fsumrecl 14928	. . . . . 6 ⊢ (𝜑 → Σ𝑖 ∈ (𝑗...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)) ∈ ℝ)
107		eluzfz2 12769	. . . . . . . . 9 ⊢ (𝑁 ∈ (ℤ_≥‘𝑗) → 𝑁 ∈ (𝑗...𝑁))
108		ne0i 4226	. . . . . . . . 9 ⊢ (𝑁 ∈ (𝑗...𝑁) → (𝑗...𝑁) ≠ ∅)
109	15, 47, 107, 108	4syl 19	. . . . . . . 8 ⊢ (𝜑 → (𝑗...𝑁) ≠ ∅)
110	23	adantr 481	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → 𝑁 ∈ ℕ)
111	90, 110	nndivred 11545	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → (𝐸 / 𝑁) ∈ ℝ)
112	90, 111	remulcld 10524	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → (𝐸 · (𝐸 / 𝑁)) ∈ ℝ)
113		stoweidlem11.6	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → ((𝑋‘𝑖)‘𝑡) < (𝐸 / 𝑁))
114	7	rpgt0d 12288	. . . . . . . . . . 11 ⊢ (𝜑 → 0 < 𝐸)
115	114	adantr 481	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → 0 < 𝐸)
116		ltmul2 11345	. . . . . . . . . 10 ⊢ ((((𝑋‘𝑖)‘𝑡) ∈ ℝ ∧ (𝐸 / 𝑁) ∈ ℝ ∧ (𝐸 ∈ ℝ ∧ 0 < 𝐸)) → (((𝑋‘𝑖)‘𝑡) < (𝐸 / 𝑁) ↔ (𝐸 · ((𝑋‘𝑖)‘𝑡)) < (𝐸 · (𝐸 / 𝑁))))
117	104, 111, 90, 115, 116	syl112anc 1367	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → (((𝑋‘𝑖)‘𝑡) < (𝐸 / 𝑁) ↔ (𝐸 · ((𝑋‘𝑖)‘𝑡)) < (𝐸 · (𝐸 / 𝑁))))
118	113, 117	mpbid 233	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑖 ∈ (𝑗...𝑁)) → (𝐸 · ((𝑋‘𝑖)‘𝑡)) < (𝐸 · (𝐸 / 𝑁)))
119	89, 109, 105, 112, 118	fsumlt 14992	. . . . . . 7 ⊢ (𝜑 → Σ𝑖 ∈ (𝑗...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)) < Σ𝑖 ∈ (𝑗...𝑁)(𝐸 · (𝐸 / 𝑁)))
120	23	nnne0d 11541	. . . . . . . . . . 11 ⊢ (𝜑 → 𝑁 ≠ 0)
121	84, 64, 120	divcld 11270	. . . . . . . . . 10 ⊢ (𝜑 → (𝐸 / 𝑁) ∈ ℂ)
122	84, 121	mulcld 10514	. . . . . . . . 9 ⊢ (𝜑 → (𝐸 · (𝐸 / 𝑁)) ∈ ℂ)
123		fsumconst 14982	. . . . . . . . 9 ⊢ (((𝑗...𝑁) ∈ Fin ∧ (𝐸 · (𝐸 / 𝑁)) ∈ ℂ) → Σ𝑖 ∈ (𝑗...𝑁)(𝐸 · (𝐸 / 𝑁)) = ((♯‘(𝑗...𝑁)) · (𝐸 · (𝐸 / 𝑁))))
124	89, 122, 123	syl2anc 584	. . . . . . . 8 ⊢ (𝜑 → Σ𝑖 ∈ (𝑗...𝑁)(𝐸 · (𝐸 / 𝑁)) = ((♯‘(𝑗...𝑁)) · (𝐸 · (𝐸 / 𝑁))))
125		hashfz 13640	. . . . . . . . . 10 ⊢ (𝑁 ∈ (ℤ_≥‘𝑗) → (♯‘(𝑗...𝑁)) = ((𝑁 − 𝑗) + 1))
126	15, 47, 125	3syl 18	. . . . . . . . 9 ⊢ (𝜑 → (♯‘(𝑗...𝑁)) = ((𝑁 − 𝑗) + 1))
127	126	oveq1d 7038	. . . . . . . 8 ⊢ (𝜑 → ((♯‘(𝑗...𝑁)) · (𝐸 · (𝐸 / 𝑁))) = (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁))))
128	124, 127	eqtrd 2833	. . . . . . 7 ⊢ (𝜑 → Σ𝑖 ∈ (𝑗...𝑁)(𝐸 · (𝐸 / 𝑁)) = (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁))))
129	119, 128	breqtrd 4994	. . . . . 6 ⊢ (𝜑 → Σ𝑖 ∈ (𝑗...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)) < (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁))))
130	106, 30, 58, 129	ltadd2dd 10652	. . . . 5 ⊢ (𝜑 → (Σ𝑖 ∈ (0...(𝑗 − 1))(𝐸 · ((𝑋‘𝑖)‘𝑡)) + Σ𝑖 ∈ (𝑗...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡))) < (Σ𝑖 ∈ (0...(𝑗 − 1))(𝐸 · ((𝑋‘𝑖)‘𝑡)) + (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁)))))
131	88, 130	eqbrtrd 4990	. . . 4 ⊢ (𝜑 → Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)) < (Σ𝑖 ∈ (0...(𝑗 − 1))(𝐸 · ((𝑋‘𝑖)‘𝑡)) + (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁)))))
132		stoweidlem11.5	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...𝑁)) → ((𝑋‘𝑖)‘𝑡) ≤ 1)
133	55, 132	syldan 591	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...(𝑗 − 1))) → ((𝑋‘𝑖)‘𝑡) ≤ 1)
134		1red 10495	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...(𝑗 − 1))) → 1 ∈ ℝ)
135	114	adantr 481	. . . . . . . . . 10 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...(𝑗 − 1))) → 0 < 𝐸)
136		lemul2 11347	. . . . . . . . . 10 ⊢ ((((𝑋‘𝑖)‘𝑡) ∈ ℝ ∧ 1 ∈ ℝ ∧ (𝐸 ∈ ℝ ∧ 0 < 𝐸)) → (((𝑋‘𝑖)‘𝑡) ≤ 1 ↔ (𝐸 · ((𝑋‘𝑖)‘𝑡)) ≤ (𝐸 · 1)))
137	56, 134, 40, 135, 136	syl112anc 1367	. . . . . . . . 9 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...(𝑗 − 1))) → (((𝑋‘𝑖)‘𝑡) ≤ 1 ↔ (𝐸 · ((𝑋‘𝑖)‘𝑡)) ≤ (𝐸 · 1)))
138	133, 137	mpbid 233	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...(𝑗 − 1))) → (𝐸 · ((𝑋‘𝑖)‘𝑡)) ≤ (𝐸 · 1))
139	84	mulid1d 10511	. . . . . . . . 9 ⊢ (𝜑 → (𝐸 · 1) = 𝐸)
140	139	adantr 481	. . . . . . . 8 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...(𝑗 − 1))) → (𝐸 · 1) = 𝐸)
141	138, 140	breqtrd 4994	. . . . . . 7 ⊢ ((𝜑 ∧ 𝑖 ∈ (0...(𝑗 − 1))) → (𝐸 · ((𝑋‘𝑖)‘𝑡)) ≤ 𝐸)
142	39, 57, 40, 141	fsumle 14991	. . . . . 6 ⊢ (𝜑 → Σ𝑖 ∈ (0...(𝑗 − 1))(𝐸 · ((𝑋‘𝑖)‘𝑡)) ≤ Σ𝑖 ∈ (0...(𝑗 − 1))𝐸)
143		fsumconst 14982	. . . . . . . 8 ⊢ (((0...(𝑗 − 1)) ∈ Fin ∧ 𝐸 ∈ ℂ) → Σ𝑖 ∈ (0...(𝑗 − 1))𝐸 = ((♯‘(0...(𝑗 − 1))) · 𝐸))
144	39, 84, 143	syl2anc 584	. . . . . . 7 ⊢ (𝜑 → Σ𝑖 ∈ (0...(𝑗 − 1))𝐸 = ((♯‘(0...(𝑗 − 1))) · 𝐸))
145		0z 11846	. . . . . . . . . . 11 ⊢ 0 ∈ ℤ
146		1e0p1 11994	. . . . . . . . . . . . 13 ⊢ 1 = (0 + 1)
147	146	fveq2i 6548	. . . . . . . . . . . 12 ⊢ (ℤ_≥‘1) = (ℤ_≥‘(0 + 1))
148	17, 147	syl6eleq 2895	. . . . . . . . . . 11 ⊢ (𝜑 → 𝑗 ∈ (ℤ_≥‘(0 + 1)))
149		eluzp1m1 12121	. . . . . . . . . . 11 ⊢ ((0 ∈ ℤ ∧ 𝑗 ∈ (ℤ_≥‘(0 + 1))) → (𝑗 − 1) ∈ (ℤ_≥‘0))
150	145, 148, 149	sylancr 587	. . . . . . . . . 10 ⊢ (𝜑 → (𝑗 − 1) ∈ (ℤ_≥‘0))
151		hashfz 13640	. . . . . . . . . 10 ⊢ ((𝑗 − 1) ∈ (ℤ_≥‘0) → (♯‘(0...(𝑗 − 1))) = (((𝑗 − 1) − 0) + 1))
152	150, 151	syl 17	. . . . . . . . 9 ⊢ (𝜑 → (♯‘(0...(𝑗 − 1))) = (((𝑗 − 1) − 0) + 1))
153	79, 65	subcld 10851	. . . . . . . . . . 11 ⊢ (𝜑 → (𝑗 − 1) ∈ ℂ)
154	153	subid1d 10840	. . . . . . . . . 10 ⊢ (𝜑 → ((𝑗 − 1) − 0) = (𝑗 − 1))
155	154	oveq1d 7038	. . . . . . . . 9 ⊢ (𝜑 → (((𝑗 − 1) − 0) + 1) = ((𝑗 − 1) + 1))
156	152, 155, 80	3eqtrd 2837	. . . . . . . 8 ⊢ (𝜑 → (♯‘(0...(𝑗 − 1))) = 𝑗)
157	156	oveq1d 7038	. . . . . . 7 ⊢ (𝜑 → ((♯‘(0...(𝑗 − 1))) · 𝐸) = (𝑗 · 𝐸))
158	79, 84	mulcomd 10515	. . . . . . 7 ⊢ (𝜑 → (𝑗 · 𝐸) = (𝐸 · 𝑗))
159	144, 157, 158	3eqtrd 2837	. . . . . 6 ⊢ (𝜑 → Σ𝑖 ∈ (0...(𝑗 − 1))𝐸 = (𝐸 · 𝑗))
160	142, 159	breqtrd 4994	. . . . 5 ⊢ (𝜑 → Σ𝑖 ∈ (0...(𝑗 − 1))(𝐸 · ((𝑋‘𝑖)‘𝑡)) ≤ (𝐸 · 𝑗))
161	58, 22, 30, 160	leadd1dd 11108	. . . 4 ⊢ (𝜑 → (Σ𝑖 ∈ (0...(𝑗 − 1))(𝐸 · ((𝑋‘𝑖)‘𝑡)) + (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁)))) ≤ ((𝐸 · 𝑗) + (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁)))))
162	14, 59, 31, 131, 161	ltletrd 10653	. . 3 ⊢ (𝜑 → Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)) < ((𝐸 · 𝑗) + (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁)))))
163	8, 8	remulcld 10524	. . . . 5 ⊢ (𝜑 → (𝐸 · 𝐸) ∈ ℝ)
164	22, 163	readdcld 10523	. . . 4 ⊢ (𝜑 → ((𝐸 · 𝑗) + (𝐸 · 𝐸)) ∈ ℝ)
165	64, 79	subcld 10851	. . . . . . . 8 ⊢ (𝜑 → (𝑁 − 𝑗) ∈ ℂ)
166	165, 65	addcld 10513	. . . . . . 7 ⊢ (𝜑 → ((𝑁 − 𝑗) + 1) ∈ ℂ)
167	84, 166, 121	mul12d 10702	. . . . . 6 ⊢ (𝜑 → (𝐸 · (((𝑁 − 𝑗) + 1) · (𝐸 / 𝑁))) = (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁))))
168	167	oveq2d 7039	. . . . 5 ⊢ (𝜑 → ((𝐸 · 𝑗) + (𝐸 · (((𝑁 − 𝑗) + 1) · (𝐸 / 𝑁)))) = ((𝐸 · 𝑗) + (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁)))))
169	27, 28	remulcld 10524	. . . . . . 7 ⊢ (𝜑 → (((𝑁 − 𝑗) + 1) · (𝐸 / 𝑁)) ∈ ℝ)
170	8, 169	remulcld 10524	. . . . . 6 ⊢ (𝜑 → (𝐸 · (((𝑁 − 𝑗) + 1) · (𝐸 / 𝑁))) ∈ ℝ)
171	166, 84, 64, 120	div12d 11306	. . . . . . . 8 ⊢ (𝜑 → (((𝑁 − 𝑗) + 1) · (𝐸 / 𝑁)) = (𝐸 · (((𝑁 − 𝑗) + 1) / 𝑁)))
172	26, 21	resubcld 10922	. . . . . . . . . . . . . 14 ⊢ (𝜑 → (1 − 𝑗) ∈ ℝ)
173		elfzle1 12764	. . . . . . . . . . . . . . . 16 ⊢ (𝑗 ∈ (1...𝑁) → 1 ≤ 𝑗)
174	15, 173	syl 17	. . . . . . . . . . . . . . 15 ⊢ (𝜑 → 1 ≤ 𝑗)
175	26, 21	suble0d 11085	. . . . . . . . . . . . . . 15 ⊢ (𝜑 → ((1 − 𝑗) ≤ 0 ↔ 1 ≤ 𝑗))
176	174, 175	mpbird 258	. . . . . . . . . . . . . 14 ⊢ (𝜑 → (1 − 𝑗) ≤ 0)
177	172, 92, 24, 176	leadd2dd 11109	. . . . . . . . . . . . 13 ⊢ (𝜑 → (𝑁 + (1 − 𝑗)) ≤ (𝑁 + 0))
178	64, 65, 79	addsub12d 10874	. . . . . . . . . . . . . 14 ⊢ (𝜑 → (𝑁 + (1 − 𝑗)) = (1 + (𝑁 − 𝑗)))
179	65, 165	addcomd 10695	. . . . . . . . . . . . . 14 ⊢ (𝜑 → (1 + (𝑁 − 𝑗)) = ((𝑁 − 𝑗) + 1))
180	178, 179	eqtrd 2833	. . . . . . . . . . . . 13 ⊢ (𝜑 → (𝑁 + (1 − 𝑗)) = ((𝑁 − 𝑗) + 1))
181	64	addid1d 10693	. . . . . . . . . . . . 13 ⊢ (𝜑 → (𝑁 + 0) = 𝑁)
182	177, 180, 181	3brtr3d 4999	. . . . . . . . . . . 12 ⊢ (𝜑 → ((𝑁 − 𝑗) + 1) ≤ 𝑁)
183	23	nngt0d 11540	. . . . . . . . . . . . 13 ⊢ (𝜑 → 0 < 𝑁)
184		lediv1 11359	. . . . . . . . . . . . 13 ⊢ ((((𝑁 − 𝑗) + 1) ∈ ℝ ∧ 𝑁 ∈ ℝ ∧ (𝑁 ∈ ℝ ∧ 0 < 𝑁)) → (((𝑁 − 𝑗) + 1) ≤ 𝑁 ↔ (((𝑁 − 𝑗) + 1) / 𝑁) ≤ (𝑁 / 𝑁)))
185	27, 24, 24, 183, 184	syl112anc 1367	. . . . . . . . . . . 12 ⊢ (𝜑 → (((𝑁 − 𝑗) + 1) ≤ 𝑁 ↔ (((𝑁 − 𝑗) + 1) / 𝑁) ≤ (𝑁 / 𝑁)))
186	182, 185	mpbid 233	. . . . . . . . . . 11 ⊢ (𝜑 → (((𝑁 − 𝑗) + 1) / 𝑁) ≤ (𝑁 / 𝑁))
187	64, 120	dividd 11268	. . . . . . . . . . 11 ⊢ (𝜑 → (𝑁 / 𝑁) = 1)
188	186, 187	breqtrd 4994	. . . . . . . . . 10 ⊢ (𝜑 → (((𝑁 − 𝑗) + 1) / 𝑁) ≤ 1)
189	27, 23	nndivred 11545	. . . . . . . . . . 11 ⊢ (𝜑 → (((𝑁 − 𝑗) + 1) / 𝑁) ∈ ℝ)
190	189, 26, 7	lemul2d 12329	. . . . . . . . . 10 ⊢ (𝜑 → ((((𝑁 − 𝑗) + 1) / 𝑁) ≤ 1 ↔ (𝐸 · (((𝑁 − 𝑗) + 1) / 𝑁)) ≤ (𝐸 · 1)))
191	188, 190	mpbid 233	. . . . . . . . 9 ⊢ (𝜑 → (𝐸 · (((𝑁 − 𝑗) + 1) / 𝑁)) ≤ (𝐸 · 1))
192	191, 139	breqtrd 4994	. . . . . . . 8 ⊢ (𝜑 → (𝐸 · (((𝑁 − 𝑗) + 1) / 𝑁)) ≤ 𝐸)
193	171, 192	eqbrtrd 4990	. . . . . . 7 ⊢ (𝜑 → (((𝑁 − 𝑗) + 1) · (𝐸 / 𝑁)) ≤ 𝐸)
194	169, 8, 7	lemul2d 12329	. . . . . . 7 ⊢ (𝜑 → ((((𝑁 − 𝑗) + 1) · (𝐸 / 𝑁)) ≤ 𝐸 ↔ (𝐸 · (((𝑁 − 𝑗) + 1) · (𝐸 / 𝑁))) ≤ (𝐸 · 𝐸)))
195	193, 194	mpbid 233	. . . . . 6 ⊢ (𝜑 → (𝐸 · (((𝑁 − 𝑗) + 1) · (𝐸 / 𝑁))) ≤ (𝐸 · 𝐸))
196	170, 163, 22, 195	leadd2dd 11109	. . . . 5 ⊢ (𝜑 → ((𝐸 · 𝑗) + (𝐸 · (((𝑁 − 𝑗) + 1) · (𝐸 / 𝑁)))) ≤ ((𝐸 · 𝑗) + (𝐸 · 𝐸)))
197	168, 196	eqbrtrrd 4992	. . . 4 ⊢ (𝜑 → ((𝐸 · 𝑗) + (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁)))) ≤ ((𝐸 · 𝑗) + (𝐸 · 𝐸)))
198	84, 79	mulcomd 10515	. . . . . . 7 ⊢ (𝜑 → (𝐸 · 𝑗) = (𝑗 · 𝐸))
199	198	oveq1d 7038	. . . . . 6 ⊢ (𝜑 → ((𝐸 · 𝑗) + (𝐸 · 𝐸)) = ((𝑗 · 𝐸) + (𝐸 · 𝐸)))
200	79, 84, 84	adddird 10519	. . . . . 6 ⊢ (𝜑 → ((𝑗 + 𝐸) · 𝐸) = ((𝑗 · 𝐸) + (𝐸 · 𝐸)))
201	199, 200	eqtr4d 2836	. . . . 5 ⊢ (𝜑 → ((𝐸 · 𝑗) + (𝐸 · 𝐸)) = ((𝑗 + 𝐸) · 𝐸))
202	21, 8	readdcld 10523	. . . . . 6 ⊢ (𝜑 → (𝑗 + 𝐸) ∈ ℝ)
203		stoweidlem11.8	. . . . . . 7 ⊢ (𝜑 → 𝐸 < (1 / 3))
204	8, 36, 21, 203	ltadd2dd 10652	. . . . . 6 ⊢ (𝜑 → (𝑗 + 𝐸) < (𝑗 + (1 / 3)))
205	202, 37, 7, 204	ltmul1dd 12340	. . . . 5 ⊢ (𝜑 → ((𝑗 + 𝐸) · 𝐸) < ((𝑗 + (1 / 3)) · 𝐸))
206	201, 205	eqbrtrd 4990	. . . 4 ⊢ (𝜑 → ((𝐸 · 𝑗) + (𝐸 · 𝐸)) < ((𝑗 + (1 / 3)) · 𝐸))
207	31, 164, 38, 197, 206	lelttrd 10651	. . 3 ⊢ (𝜑 → ((𝐸 · 𝑗) + (((𝑁 − 𝑗) + 1) · (𝐸 · (𝐸 / 𝑁)))) < ((𝑗 + (1 / 3)) · 𝐸))
208	14, 31, 38, 162, 207	lttrd 10654	. 2 ⊢ (𝜑 → Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)) < ((𝑗 + (1 / 3)) · 𝐸))
209	5, 208	eqbrtrd 4990	1 ⊢ (𝜑 → ((𝑡 ∈ 𝑇 ↦ Σ𝑖 ∈ (0...𝑁)(𝐸 · ((𝑋‘𝑖)‘𝑡)))‘𝑡) < ((𝑗 + (1 / 3)) · 𝐸))

Colors of variables: wff setvar class

Syntax hints: → wi 4 ↔ wb 207 ∧ wa 396 ∧ w3a 1080 = wceq 1525 ∈ wcel 2083 ≠ wne 2986 Vcvv 3440 ∪ cun 3863 ∩ cin 3864 ⊆ wss 3865 ∅c0 4217 class class class wbr 4968 ↦ cmpt 5047 ⟶wf 6228 ‘cfv 6232 (class class class)co 7023 Fincfn 8364 ℂcc 10388 ℝcr 10389 0cc0 10390 1c1 10391 + caddc 10393 · cmul 10395 < clt 10528 ≤ cle 10529 − cmin 10723 / cdiv 11151 ℕcn 11492 3c3 11547 ℤcz 11835 ℤ_≥cuz 12097 ℝ⁺crp 12243 ...cfz 12746 ♯chash 13544 Σcsu 14880

This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1781 ax-4 1795 ax-5 1892 ax-6 1951 ax-7 1996 ax-8 2085 ax-9 2093 ax-10 2114 ax-11 2128 ax-12 2143 ax-13 2346 ax-ext 2771 ax-rep 5088 ax-sep 5101 ax-nul 5108 ax-pow 5164 ax-pr 5228 ax-un 7326 ax-inf2 8957 ax-cnex 10446 ax-resscn 10447 ax-1cn 10448 ax-icn 10449 ax-addcl 10450 ax-addrcl 10451 ax-mulcl 10452 ax-mulrcl 10453 ax-mulcom 10454 ax-addass 10455 ax-mulass 10456 ax-distr 10457 ax-i2m1 10458 ax-1ne0 10459 ax-1rid 10460 ax-rnegex 10461 ax-rrecex 10462 ax-cnre 10463 ax-pre-lttri 10464 ax-pre-lttrn 10465 ax-pre-ltadd 10466 ax-pre-mulgt0 10467 ax-pre-sup 10468

This theorem depends on definitions: df-bi 208 df-an 397 df-or 843 df-3or 1081 df-3an 1082 df-tru 1528 df-fal 1538 df-ex 1766 df-nf 1770 df-sb 2045 df-mo 2578 df-eu 2614 df-clab 2778 df-cleq 2790 df-clel 2865 df-nfc 2937 df-ne 2987 df-nel 3093 df-ral 3112 df-rex 3113 df-reu 3114 df-rmo 3115 df-rab 3116 df-v 3442 df-sbc 3712 df-csb 3818 df-dif 3868 df-un 3870 df-in 3872 df-ss 3880 df-pss 3882 df-nul 4218 df-if 4388 df-pw 4461 df-sn 4479 df-pr 4481 df-tp 4483 df-op 4485 df-uni 4752 df-int 4789 df-iun 4833 df-br 4969 df-opab 5031 df-mpt 5048 df-tr 5071 df-id 5355 df-eprel 5360 df-po 5369 df-so 5370 df-fr 5409 df-se 5410 df-we 5411 df-xp 5456 df-rel 5457 df-cnv 5458 df-co 5459 df-dm 5460 df-rn 5461 df-res 5462 df-ima 5463 df-pred 6030 df-ord 6076 df-on 6077 df-lim 6078 df-suc 6079 df-iota 6196 df-fun 6234 df-fn 6235 df-f 6236 df-f1 6237 df-fo 6238 df-f1o 6239 df-fv 6240 df-isom 6241 df-riota 6984 df-ov 7026 df-oprab 7027 df-mpo 7028 df-om 7444 df-1st 7552 df-2nd 7553 df-wrecs 7805 df-recs 7867 df-rdg 7905 df-1o 7960 df-oadd 7964 df-er 8146 df-en 8365 df-dom 8366 df-sdom 8367 df-fin 8368 df-sup 8759 df-oi 8827 df-card 9221 df-pnf 10530 df-mnf 10531 df-xr 10532 df-ltxr 10533 df-le 10534 df-sub 10725 df-neg 10726 df-div 11152 df-nn 11493 df-2 11554 df-3 11555 df-n0 11752 df-z 11836 df-uz 12098 df-rp 12244 df-ico 12598 df-fz 12747 df-fzo 12888 df-seq 13224 df-exp 13284 df-hash 13545 df-cj 14296 df-re 14297 df-im 14298 df-sqrt 14432 df-abs 14433 df-clim 14683 df-sum 14881

This theorem is referenced by: stoweidlem34 41883

W3C validator