Metamath Proof Explorer


Theorem ovnovollem1

Description: if F is a cover of B in RR , then I is the corresponding cover in the space of 1-dimensional reals. (Contributed by Glauco Siliprandi, 3-Mar-2021)

Ref Expression
Hypotheses ovnovollem1.a ⊢ φ → A ∈ V
ovnovollem1.f ⊢ φ → F ∈ ℝ 2 ℕ
ovnovollem1.i ⊢ I = j ∈ ℕ ⟼ A F ⁡ j
ovnovollem1.s ⊢ φ → B ⊆ ⋃ ran ⁡ . ∘ F
ovnovollem1.b ⊢ φ → B ∈ W
ovnovollem1.z ⊢ φ → Z = sum^ ⁡ vol ∘ . ∘ F
Assertion ovnovollem1 ⊢ φ → ∃ i ∈ ℝ 2 A ℕ B A ⊆ ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ i ⁡ j ⁡ k ∧ Z = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ i ⁡ j ⁡ k

Proof

Step Hyp Ref Expression
1 ovnovollem1.a ⊢ φ → A ∈ V
2 ovnovollem1.f ⊢ φ → F ∈ ℝ 2 ℕ
3 ovnovollem1.i ⊢ I = j ∈ ℕ ⟼ A F ⁡ j
4 ovnovollem1.s ⊢ φ → B ⊆ ⋃ ran ⁡ . ∘ F
5 ovnovollem1.b ⊢ φ → B ∈ W
6 ovnovollem1.z ⊢ φ → Z = sum^ ⁡ vol ∘ . ∘ F
7 eqidd ⊢ φ ∧ j ∈ ℕ → A F ⁡ j = A F ⁡ j
8 1 adantr ⊢ φ ∧ j ∈ ℕ → A ∈ V
9 elmapi ⊢ F ∈ ℝ 2 ℕ → F : ℕ ⟶ ℝ 2
10 2 9 syl ⊢ φ → F : ℕ ⟶ ℝ 2
11 10 ffvelcdmda ⊢ φ ∧ j ∈ ℕ → F ⁡ j ∈ ℝ 2
12 fsng ⊢ A ∈ V ∧ F ⁡ j ∈ ℝ 2 → A F ⁡ j : A ⟶ F ⁡ j ↔ A F ⁡ j = A F ⁡ j
13 8 11 12 syl2anc ⊢ φ ∧ j ∈ ℕ → A F ⁡ j : A ⟶ F ⁡ j ↔ A F ⁡ j = A F ⁡ j
14 7 13 mpbird ⊢ φ ∧ j ∈ ℕ → A F ⁡ j : A ⟶ F ⁡ j
15 11 snssd ⊢ φ ∧ j ∈ ℕ → F ⁡ j ⊆ ℝ 2
16 14 15 fssd ⊢ φ ∧ j ∈ ℕ → A F ⁡ j : A ⟶ ℝ 2
17 reex ⊢ ℝ ∈ V
18 17 17 xpex ⊢ ℝ 2 ∈ V
19 18 a1i ⊢ φ ∧ j ∈ ℕ → ℝ 2 ∈ V
20 snex ⊢ A ∈ V
21 20 a1i ⊢ φ ∧ j ∈ ℕ → A ∈ V
22 19 21 elmapd ⊢ φ ∧ j ∈ ℕ → A F ⁡ j ∈ ℝ 2 A ↔ A F ⁡ j : A ⟶ ℝ 2
23 16 22 mpbird ⊢ φ ∧ j ∈ ℕ → A F ⁡ j ∈ ℝ 2 A
24 23 3 fmptd ⊢ φ → I : ℕ ⟶ ℝ 2 A
25 ovexd ⊢ φ → ℝ 2 A ∈ V
26 nnex ⊢ ℕ ∈ V
27 26 a1i ⊢ φ → ℕ ∈ V
28 25 27 elmapd ⊢ φ → I ∈ ℝ 2 A ℕ ↔ I : ℕ ⟶ ℝ 2 A
29 24 28 mpbird ⊢ φ → I ∈ ℝ 2 A ℕ
30 icof ⊢ . : ℝ * × ℝ * ⟶ 𝒫 ℝ *
31 30 a1i ⊢ φ → . : ℝ * × ℝ * ⟶ 𝒫 ℝ *
32 rexpssxrxp ⊢ ℝ 2 ⊆ ℝ * × ℝ *
33 32 a1i ⊢ φ → ℝ 2 ⊆ ℝ * × ℝ *
34 31 33 10 fcoss ⊢ φ → . ∘ F : ℕ ⟶ 𝒫 ℝ *
35 34 ffnd ⊢ φ → . ∘ F Fn ℕ
36 fniunfv ⊢ . ∘ F Fn ℕ → ⋃ j ∈ ℕ . ∘ F ⁡ j = ⋃ ran ⁡ . ∘ F
37 35 36 syl ⊢ φ → ⋃ j ∈ ℕ . ∘ F ⁡ j = ⋃ ran ⁡ . ∘ F
38 37 eqcomd ⊢ φ → ⋃ ran ⁡ . ∘ F = ⋃ j ∈ ℕ . ∘ F ⁡ j
39 4 38 sseqtrd ⊢ φ → B ⊆ ⋃ j ∈ ℕ . ∘ F ⁡ j
40 fvex ⊢ . ∘ F ⁡ j ∈ V
41 26 40 iunex ⊢ ⋃ j ∈ ℕ . ∘ F ⁡ j ∈ V
42 41 a1i ⊢ φ → ⋃ j ∈ ℕ . ∘ F ⁡ j ∈ V
43 20 a1i ⊢ φ → A ∈ V
44 1 snn0d ⊢ φ → A ≠ ∅
45 5 42 43 44 mapss2 ⊢ φ → B ⊆ ⋃ j ∈ ℕ . ∘ F ⁡ j ↔ B A ⊆ ⋃ j ∈ ℕ . ∘ F ⁡ j A
46 39 45 mpbid ⊢ φ → B A ⊆ ⋃ j ∈ ℕ . ∘ F ⁡ j A
47 nfv ⊢ Ⅎ j φ
48 fvexd ⊢ φ ∧ j ∈ ℕ → . ⁡ F ⁡ j ∈ V
49 47 27 48 1 iunmapsn ⊢ φ → ⋃ j ∈ ℕ . ⁡ F ⁡ j A = ⋃ j ∈ ℕ . ⁡ F ⁡ j A
50 49 eqcomd ⊢ φ → ⋃ j ∈ ℕ . ⁡ F ⁡ j A = ⋃ j ∈ ℕ . ⁡ F ⁡ j A
51 elmapfun ⊢ F ∈ ℝ 2 ℕ → Fun ⁡ F
52 2 51 syl ⊢ φ → Fun ⁡ F
53 52 adantr ⊢ φ ∧ j ∈ ℕ → Fun ⁡ F
54 simpr ⊢ φ ∧ j ∈ ℕ → j ∈ ℕ
55 10 fdmd ⊢ φ → dom ⁡ F = ℕ
56 55 eqcomd ⊢ φ → ℕ = dom ⁡ F
57 56 adantr ⊢ φ ∧ j ∈ ℕ → ℕ = dom ⁡ F
58 54 57 eleqtrd ⊢ φ ∧ j ∈ ℕ → j ∈ dom ⁡ F
59 fvco ⊢ Fun ⁡ F ∧ j ∈ dom ⁡ F → . ∘ F ⁡ j = . ⁡ F ⁡ j
60 53 58 59 syl2anc ⊢ φ ∧ j ∈ ℕ → . ∘ F ⁡ j = . ⁡ F ⁡ j
61 60 iuneq2dv ⊢ φ → ⋃ j ∈ ℕ . ∘ F ⁡ j = ⋃ j ∈ ℕ . ⁡ F ⁡ j
62 61 oveq1d ⊢ φ → ⋃ j ∈ ℕ . ∘ F ⁡ j A = ⋃ j ∈ ℕ . ⁡ F ⁡ j A
63 14 ffund ⊢ φ ∧ j ∈ ℕ → Fun ⁡ A F ⁡ j
64 id ⊢ j ∈ ℕ → j ∈ ℕ
65 snex ⊢ A F ⁡ j ∈ V
66 65 a1i ⊢ j ∈ ℕ → A F ⁡ j ∈ V
67 3 fvmpt2 ⊢ j ∈ ℕ ∧ A F ⁡ j ∈ V → I ⁡ j = A F ⁡ j
68 64 66 67 syl2anc ⊢ j ∈ ℕ → I ⁡ j = A F ⁡ j
69 68 adantl ⊢ φ ∧ j ∈ ℕ → I ⁡ j = A F ⁡ j
70 69 funeqd ⊢ φ ∧ j ∈ ℕ → Fun ⁡ I ⁡ j ↔ Fun ⁡ A F ⁡ j
71 63 70 mpbird ⊢ φ ∧ j ∈ ℕ → Fun ⁡ I ⁡ j
72 71 adantr ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → Fun ⁡ I ⁡ j
73 simpr ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → k ∈ A
74 69 dmeqd ⊢ φ ∧ j ∈ ℕ → dom ⁡ I ⁡ j = dom ⁡ A F ⁡ j
75 14 fdmd ⊢ φ ∧ j ∈ ℕ → dom ⁡ A F ⁡ j = A
76 74 75 eqtrd ⊢ φ ∧ j ∈ ℕ → dom ⁡ I ⁡ j = A
77 76 eleq2d ⊢ φ ∧ j ∈ ℕ → k ∈ dom ⁡ I ⁡ j ↔ k ∈ A
78 77 adantr ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → k ∈ dom ⁡ I ⁡ j ↔ k ∈ A
79 73 78 mpbird ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → k ∈ dom ⁡ I ⁡ j
80 fvco ⊢ Fun ⁡ I ⁡ j ∧ k ∈ dom ⁡ I ⁡ j → . ∘ I ⁡ j ⁡ k = . ⁡ I ⁡ j ⁡ k
81 72 79 80 syl2anc ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → . ∘ I ⁡ j ⁡ k = . ⁡ I ⁡ j ⁡ k
82 68 fveq1d ⊢ j ∈ ℕ → I ⁡ j ⁡ k = A F ⁡ j ⁡ k
83 82 ad2antlr ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → I ⁡ j ⁡ k = A F ⁡ j ⁡ k
84 elsni ⊢ k ∈ A → k = A
85 84 fveq2d ⊢ k ∈ A → A F ⁡ j ⁡ k = A F ⁡ j ⁡ A
86 85 adantl ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → A F ⁡ j ⁡ k = A F ⁡ j ⁡ A
87 fvexd ⊢ φ → F ⁡ j ∈ V
88 fvsng ⊢ A ∈ V ∧ F ⁡ j ∈ V → A F ⁡ j ⁡ A = F ⁡ j
89 1 87 88 syl2anc ⊢ φ → A F ⁡ j ⁡ A = F ⁡ j
90 89 ad2antrr ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → A F ⁡ j ⁡ A = F ⁡ j
91 83 86 90 3eqtrd ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → I ⁡ j ⁡ k = F ⁡ j
92 91 fveq2d ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → . ⁡ I ⁡ j ⁡ k = . ⁡ F ⁡ j
93 eqidd ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → . ⁡ F ⁡ j = . ⁡ F ⁡ j
94 81 92 93 3eqtrd ⊢ φ ∧ j ∈ ℕ ∧ k ∈ A → . ∘ I ⁡ j ⁡ k = . ⁡ F ⁡ j
95 94 ixpeq2dva ⊢ φ ∧ j ∈ ℕ → ⨉ k ∈ A . ∘ I ⁡ j ⁡ k = ⨉ k ∈ A . ⁡ F ⁡ j
96 fvex ⊢ . ⁡ F ⁡ j ∈ V
97 20 96 ixpconst ⊢ ⨉ k ∈ A . ⁡ F ⁡ j = . ⁡ F ⁡ j A
98 97 a1i ⊢ φ ∧ j ∈ ℕ → ⨉ k ∈ A . ⁡ F ⁡ j = . ⁡ F ⁡ j A
99 95 98 eqtrd ⊢ φ ∧ j ∈ ℕ → ⨉ k ∈ A . ∘ I ⁡ j ⁡ k = . ⁡ F ⁡ j A
100 99 iuneq2dv ⊢ φ → ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ I ⁡ j ⁡ k = ⋃ j ∈ ℕ . ⁡ F ⁡ j A
101 50 62 100 3eqtr4d ⊢ φ → ⋃ j ∈ ℕ . ∘ F ⁡ j A = ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ I ⁡ j ⁡ k
102 46 101 sseqtrd ⊢ φ → B A ⊆ ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ I ⁡ j ⁡ k
103 nfcv ⊢ Ⅎ _ j F
104 ressxr ⊢ ℝ ⊆ ℝ *
105 xpss2 ⊢ ℝ ⊆ ℝ * → ℝ 2 ⊆ ℝ × ℝ *
106 104 105 ax-mp ⊢ ℝ 2 ⊆ ℝ × ℝ *
107 106 a1i ⊢ φ → ℝ 2 ⊆ ℝ × ℝ *
108 10 107 fssd ⊢ φ → F : ℕ ⟶ ℝ × ℝ *
109 103 108 volicofmpt ⊢ φ → vol ∘ . ∘ F = j ∈ ℕ ⟼ vol ⁡ 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j
110 68 coeq2d ⊢ j ∈ ℕ → . ∘ I ⁡ j = . ∘ A F ⁡ j
111 110 fveq1d ⊢ j ∈ ℕ → . ∘ I ⁡ j ⁡ A = . ∘ A F ⁡ j ⁡ A
112 111 adantl ⊢ φ ∧ j ∈ ℕ → . ∘ I ⁡ j ⁡ A = . ∘ A F ⁡ j ⁡ A
113 snidg ⊢ A ∈ V → A ∈ A
114 1 113 syl ⊢ φ → A ∈ A
115 dmsnopg ⊢ F ⁡ j ∈ V → dom ⁡ A F ⁡ j = A
116 87 115 syl ⊢ φ → dom ⁡ A F ⁡ j = A
117 114 116 eleqtrrd ⊢ φ → A ∈ dom ⁡ A F ⁡ j
118 117 adantr ⊢ φ ∧ j ∈ ℕ → A ∈ dom ⁡ A F ⁡ j
119 fvco ⊢ Fun ⁡ A F ⁡ j ∧ A ∈ dom ⁡ A F ⁡ j → . ∘ A F ⁡ j ⁡ A = . ⁡ A F ⁡ j ⁡ A
120 63 118 119 syl2anc ⊢ φ ∧ j ∈ ℕ → . ∘ A F ⁡ j ⁡ A = . ⁡ A F ⁡ j ⁡ A
121 fvexd ⊢ φ ∧ j ∈ ℕ → F ⁡ j ∈ V
122 8 121 88 syl2anc ⊢ φ ∧ j ∈ ℕ → A F ⁡ j ⁡ A = F ⁡ j
123 1st2nd2 ⊢ F ⁡ j ∈ ℝ 2 → F ⁡ j = 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j
124 11 123 syl ⊢ φ ∧ j ∈ ℕ → F ⁡ j = 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j
125 122 124 eqtrd ⊢ φ ∧ j ∈ ℕ → A F ⁡ j ⁡ A = 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j
126 125 fveq2d ⊢ φ ∧ j ∈ ℕ → . ⁡ A F ⁡ j ⁡ A = . ⁡ 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j
127 df-ov ⊢ 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j = . ⁡ 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j
128 127 eqcomi ⊢ . ⁡ 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j = 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j
129 128 a1i ⊢ φ ∧ j ∈ ℕ → . ⁡ 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j = 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j
130 126 129 eqtrd ⊢ φ ∧ j ∈ ℕ → . ⁡ A F ⁡ j ⁡ A = 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j
131 112 120 130 3eqtrd ⊢ φ ∧ j ∈ ℕ → . ∘ I ⁡ j ⁡ A = 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j
132 131 fveq2d ⊢ φ ∧ j ∈ ℕ → vol ⁡ . ∘ I ⁡ j ⁡ A = vol ⁡ 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j
133 xp1st ⊢ F ⁡ j ∈ ℝ 2 → 1 st ⁡ F ⁡ j ∈ ℝ
134 11 133 syl ⊢ φ ∧ j ∈ ℕ → 1 st ⁡ F ⁡ j ∈ ℝ
135 xp2nd ⊢ F ⁡ j ∈ ℝ 2 → 2 nd ⁡ F ⁡ j ∈ ℝ
136 11 135 syl ⊢ φ ∧ j ∈ ℕ → 2 nd ⁡ F ⁡ j ∈ ℝ
137 volicore ⊢ 1 st ⁡ F ⁡ j ∈ ℝ ∧ 2 nd ⁡ F ⁡ j ∈ ℝ → vol ⁡ 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j ∈ ℝ
138 134 136 137 syl2anc ⊢ φ ∧ j ∈ ℕ → vol ⁡ 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j ∈ ℝ
139 132 138 eqeltrd ⊢ φ ∧ j ∈ ℕ → vol ⁡ . ∘ I ⁡ j ⁡ A ∈ ℝ
140 139 recnd ⊢ φ ∧ j ∈ ℕ → vol ⁡ . ∘ I ⁡ j ⁡ A ∈ ℂ
141 2fveq3 ⊢ k = A → vol ⁡ . ∘ I ⁡ j ⁡ k = vol ⁡ . ∘ I ⁡ j ⁡ A
142 141 prodsn ⊢ A ∈ V ∧ vol ⁡ . ∘ I ⁡ j ⁡ A ∈ ℂ → ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k = vol ⁡ . ∘ I ⁡ j ⁡ A
143 8 140 142 syl2anc ⊢ φ ∧ j ∈ ℕ → ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k = vol ⁡ . ∘ I ⁡ j ⁡ A
144 143 132 eqtr2d ⊢ φ ∧ j ∈ ℕ → vol ⁡ 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j = ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k
145 144 mpteq2dva ⊢ φ → j ∈ ℕ ⟼ vol ⁡ 1 st ⁡ F ⁡ j 2 nd ⁡ F ⁡ j = j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k
146 109 145 eqtrd ⊢ φ → vol ∘ . ∘ F = j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k
147 146 fveq2d ⊢ φ → sum^ ⁡ vol ∘ . ∘ F = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k
148 6 147 eqtrd ⊢ φ → Z = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k
149 102 148 jca ⊢ φ → B A ⊆ ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ I ⁡ j ⁡ k ∧ Z = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k
150 fveq1 ⊢ i = I → i ⁡ j = I ⁡ j
151 150 coeq2d ⊢ i = I → . ∘ i ⁡ j = . ∘ I ⁡ j
152 151 fveq1d ⊢ i = I → . ∘ i ⁡ j ⁡ k = . ∘ I ⁡ j ⁡ k
153 152 ixpeq2dv ⊢ i = I → ⨉ k ∈ A . ∘ i ⁡ j ⁡ k = ⨉ k ∈ A . ∘ I ⁡ j ⁡ k
154 153 iuneq2d ⊢ i = I → ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ i ⁡ j ⁡ k = ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ I ⁡ j ⁡ k
155 154 sseq2d ⊢ i = I → B A ⊆ ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ i ⁡ j ⁡ k ↔ B A ⊆ ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ I ⁡ j ⁡ k
156 simpl ⊢ i = I ∧ k ∈ A → i = I
157 156 fveq1d ⊢ i = I ∧ k ∈ A → i ⁡ j = I ⁡ j
158 157 coeq2d ⊢ i = I ∧ k ∈ A → . ∘ i ⁡ j = . ∘ I ⁡ j
159 158 fveq1d ⊢ i = I ∧ k ∈ A → . ∘ i ⁡ j ⁡ k = . ∘ I ⁡ j ⁡ k
160 159 fveq2d ⊢ i = I ∧ k ∈ A → vol ⁡ . ∘ i ⁡ j ⁡ k = vol ⁡ . ∘ I ⁡ j ⁡ k
161 160 prodeq2dv ⊢ i = I → ∏ k ∈ A vol ⁡ . ∘ i ⁡ j ⁡ k = ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k
162 161 mpteq2dv ⊢ i = I → j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ i ⁡ j ⁡ k = j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k
163 162 fveq2d ⊢ i = I → sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ i ⁡ j ⁡ k = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k
164 163 eqeq2d ⊢ i = I → Z = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ i ⁡ j ⁡ k ↔ Z = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k
165 155 164 anbi12d ⊢ i = I → B A ⊆ ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ i ⁡ j ⁡ k ∧ Z = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ i ⁡ j ⁡ k ↔ B A ⊆ ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ I ⁡ j ⁡ k ∧ Z = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k
166 165 rspcev ⊢ I ∈ ℝ 2 A ℕ ∧ B A ⊆ ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ I ⁡ j ⁡ k ∧ Z = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ I ⁡ j ⁡ k → ∃ i ∈ ℝ 2 A ℕ B A ⊆ ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ i ⁡ j ⁡ k ∧ Z = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ i ⁡ j ⁡ k
167 29 149 166 syl2anc ⊢ φ → ∃ i ∈ ℝ 2 A ℕ B A ⊆ ⋃ j ∈ ℕ ⨉ k ∈ A . ∘ i ⁡ j ⁡ k ∧ Z = sum^ ⁡ j ∈ ℕ ⟼ ∏ k ∈ A vol ⁡ . ∘ i ⁡ j ⁡ k