Metamath Proof Explorer


Theorem dyadmbl

Description: Any union of dyadic rational intervals is measurable. (Contributed by Mario Carneiro, 26-Mar-2015)

Ref Expression
Hypotheses dyadmbl.1 F = x , y 0 x 2 y x + 1 2 y
dyadmbl.2 G = z A | w A . z . w z = w
dyadmbl.3 φ A ran F
Assertion dyadmbl φ . A dom vol

Proof

Step Hyp Ref Expression
1 dyadmbl.1 F = x , y 0 x 2 y x + 1 2 y
2 dyadmbl.2 G = z A | w A . z . w z = w
3 dyadmbl.3 φ A ran F
4 1 2 3 dyadmbllem φ . A = . G
5 isfinite G Fin G ω
6 iccf . : * × * 𝒫 *
7 ffun . : * × * 𝒫 * Fun .
8 funiunfv Fun . n G . n = . G
9 6 7 8 mp2b n G . n = . G
10 simpr φ G Fin G Fin
11 2 ssrab3 G A
12 11 3 sstrid φ G ran F
13 1 dyadf F : × 0 2
14 frn F : × 0 2 ran F 2
15 13 14 ax-mp ran F 2
16 inss2 2 2
17 15 16 sstri ran F 2
18 12 17 sstrdi φ G 2
19 18 adantr φ G Fin G 2
20 19 sselda φ G Fin n G n 2
21 1st2nd2 n 2 n = 1 st n 2 nd n
22 20 21 syl φ G Fin n G n = 1 st n 2 nd n
23 22 fveq2d φ G Fin n G . n = . 1 st n 2 nd n
24 df-ov 1 st n 2 nd n = . 1 st n 2 nd n
25 23 24 eqtr4di φ G Fin n G . n = 1 st n 2 nd n
26 xp1st n 2 1 st n
27 20 26 syl φ G Fin n G 1 st n
28 xp2nd n 2 2 nd n
29 20 28 syl φ G Fin n G 2 nd n
30 iccmbl 1 st n 2 nd n 1 st n 2 nd n dom vol
31 27 29 30 syl2anc φ G Fin n G 1 st n 2 nd n dom vol
32 25 31 eqeltrd φ G Fin n G . n dom vol
33 32 ralrimiva φ G Fin n G . n dom vol
34 finiunmbl G Fin n G . n dom vol n G . n dom vol
35 10 33 34 syl2anc φ G Fin n G . n dom vol
36 9 35 eqeltrrid φ G Fin . G dom vol
37 5 36 sylan2br φ G ω . G dom vol
38 rnco2 ran . f = . ran f
39 f1ofo f : 1-1 onto G f : onto G
40 39 adantl φ f : 1-1 onto G f : onto G
41 forn f : onto G ran f = G
42 40 41 syl φ f : 1-1 onto G ran f = G
43 42 imaeq2d φ f : 1-1 onto G . ran f = . G
44 38 43 syl5eq φ f : 1-1 onto G ran . f = . G
45 44 unieqd φ f : 1-1 onto G ran . f = . G
46 f1of f : 1-1 onto G f : G
47 12 15 sstrdi φ G 2
48 fss f : G G 2 f : 2
49 46 47 48 syl2anr φ f : 1-1 onto G f : 2
50 fss f : G G ran F f : ran F
51 46 12 50 syl2anr φ f : 1-1 onto G f : ran F
52 simpl a b a
53 ffvelrn f : ran F a f a ran F
54 51 52 53 syl2an φ f : 1-1 onto G a b f a ran F
55 simpr a b b
56 ffvelrn f : ran F b f b ran F
57 51 55 56 syl2an φ f : 1-1 onto G a b f b ran F
58 1 dyaddisj f a ran F f b ran F . f a . f b . f b . f a . f a . f b =
59 54 57 58 syl2anc φ f : 1-1 onto G a b . f a . f b . f b . f a . f a . f b =
60 fveq2 w = f b . w = . f b
61 60 sseq2d w = f b . f a . w . f a . f b
62 eqeq2 w = f b f a = w f a = f b
63 61 62 imbi12d w = f b . f a . w f a = w . f a . f b f a = f b
64 46 adantl φ f : 1-1 onto G f : G
65 ffvelrn f : G a f a G
66 64 52 65 syl2an φ f : 1-1 onto G a b f a G
67 fveq2 z = f a . z = . f a
68 67 sseq1d z = f a . z . w . f a . w
69 eqeq1 z = f a z = w f a = w
70 68 69 imbi12d z = f a . z . w z = w . f a . w f a = w
71 70 ralbidv z = f a w A . z . w z = w w A . f a . w f a = w
72 71 2 elrab2 f a G f a A w A . f a . w f a = w
73 72 simprbi f a G w A . f a . w f a = w
74 66 73 syl φ f : 1-1 onto G a b w A . f a . w f a = w
75 ffvelrn f : G b f b G
76 64 55 75 syl2an φ f : 1-1 onto G a b f b G
77 11 76 sseldi φ f : 1-1 onto G a b f b A
78 63 74 77 rspcdva φ f : 1-1 onto G a b . f a . f b f a = f b
79 f1of1 f : 1-1 onto G f : 1-1 G
80 79 adantl φ f : 1-1 onto G f : 1-1 G
81 f1fveq f : 1-1 G a b f a = f b a = b
82 80 81 sylan φ f : 1-1 onto G a b f a = f b a = b
83 orc a = b a = b . f a . f b =
84 82 83 syl6bi φ f : 1-1 onto G a b f a = f b a = b . f a . f b =
85 78 84 syld φ f : 1-1 onto G a b . f a . f b a = b . f a . f b =
86 fveq2 w = f a . w = . f a
87 86 sseq2d w = f a . f b . w . f b . f a
88 eqeq2 w = f a f b = w f b = f a
89 eqcom f b = f a f a = f b
90 88 89 bitrdi w = f a f b = w f a = f b
91 87 90 imbi12d w = f a . f b . w f b = w . f b . f a f a = f b
92 fveq2 z = f b . z = . f b
93 92 sseq1d z = f b . z . w . f b . w
94 eqeq1 z = f b z = w f b = w
95 93 94 imbi12d z = f b . z . w z = w . f b . w f b = w
96 95 ralbidv z = f b w A . z . w z = w w A . f b . w f b = w
97 96 2 elrab2 f b G f b A w A . f b . w f b = w
98 97 simprbi f b G w A . f b . w f b = w
99 76 98 syl φ f : 1-1 onto G a b w A . f b . w f b = w
100 11 66 sseldi φ f : 1-1 onto G a b f a A
101 91 99 100 rspcdva φ f : 1-1 onto G a b . f b . f a f a = f b
102 101 84 syld φ f : 1-1 onto G a b . f b . f a a = b . f a . f b =
103 olc . f a . f b = a = b . f a . f b =
104 103 a1i φ f : 1-1 onto G a b . f a . f b = a = b . f a . f b =
105 85 102 104 3jaod φ f : 1-1 onto G a b . f a . f b . f b . f a . f a . f b = a = b . f a . f b =
106 59 105 mpd φ f : 1-1 onto G a b a = b . f a . f b =
107 106 ralrimivva φ f : 1-1 onto G a b a = b . f a . f b =
108 2fveq3 a = b . f a = . f b
109 108 disjor Disj a . f a a b a = b . f a . f b =
110 107 109 sylibr φ f : 1-1 onto G Disj a . f a
111 eqid seq 1 + abs f = seq 1 + abs f
112 49 110 111 uniiccmbl φ f : 1-1 onto G ran . f dom vol
113 45 112 eqeltrrd φ f : 1-1 onto G . G dom vol
114 113 ex φ f : 1-1 onto G . G dom vol
115 114 exlimdv φ f f : 1-1 onto G . G dom vol
116 nnenom ω
117 ensym G ω ω G
118 entr ω ω G G
119 116 117 118 sylancr G ω G
120 bren G f f : 1-1 onto G
121 119 120 sylib G ω f f : 1-1 onto G
122 115 121 impel φ G ω . G dom vol
123 reex V
124 123 123 xpex 2 V
125 124 inex2 2 V
126 125 15 ssexi ran F V
127 ssdomg ran F V G ran F G ran F
128 126 12 127 mpsyl φ G ran F
129 omelon ω On
130 znnen
131 130 116 entri ω
132 nn0ennn 0
133 132 116 entri 0 ω
134 xpen ω 0 ω × 0 ω × ω
135 131 133 134 mp2an × 0 ω × ω
136 xpomen ω × ω ω
137 135 136 entri × 0 ω
138 137 ensymi ω × 0
139 isnumi ω On ω × 0 × 0 dom card
140 129 138 139 mp2an × 0 dom card
141 ffn F : × 0 2 F Fn × 0
142 13 141 ax-mp F Fn × 0
143 dffn4 F Fn × 0 F : × 0 onto ran F
144 142 143 mpbi F : × 0 onto ran F
145 fodomnum × 0 dom card F : × 0 onto ran F ran F × 0
146 140 144 145 mp2 ran F × 0
147 domentr ran F × 0 × 0 ω ran F ω
148 146 137 147 mp2an ran F ω
149 domtr G ran F ran F ω G ω
150 128 148 149 sylancl φ G ω
151 brdom2 G ω G ω G ω
152 150 151 sylib φ G ω G ω
153 37 122 152 mpjaodan φ . G dom vol
154 4 153 eqeltrd φ . A dom vol