Metamath Proof Explorer


Theorem cnfcom3

Description: Any infinite ordinal B is equinumerous to a power of _om . (We are being careful here to show explicit bijections rather than simple equinumerosity because we want a uniform construction for cnfcom3c .) (Contributed by Mario Carneiro, 28-May-2015) (Revised by AV, 4-Jul-2019)

Ref Expression
Hypotheses cnfcom.s S = dom ω CNF A
cnfcom.a φ A On
cnfcom.b φ B ω 𝑜 A
cnfcom.f F = ω CNF A -1 B
cnfcom.g G = OrdIso E F supp
cnfcom.h H = seq ω k V , z V M + 𝑜 z
cnfcom.t T = seq ω k V , f V K
cnfcom.m M = ω 𝑜 G k 𝑜 F G k
cnfcom.k K = x M dom f + 𝑜 x x dom f M + 𝑜 x -1
cnfcom.w W = G dom G
cnfcom3.1 φ ω B
cnfcom.x X = u F W , v ω 𝑜 W F W 𝑜 v + 𝑜 u
cnfcom.y Y = u F W , v ω 𝑜 W ω 𝑜 W 𝑜 u + 𝑜 v
cnfcom.n N = X Y -1 T dom G
Assertion cnfcom3 φ N : B 1-1 onto ω 𝑜 W

Proof

Step Hyp Ref Expression
1 cnfcom.s S = dom ω CNF A
2 cnfcom.a φ A On
3 cnfcom.b φ B ω 𝑜 A
4 cnfcom.f F = ω CNF A -1 B
5 cnfcom.g G = OrdIso E F supp
6 cnfcom.h H = seq ω k V , z V M + 𝑜 z
7 cnfcom.t T = seq ω k V , f V K
8 cnfcom.m M = ω 𝑜 G k 𝑜 F G k
9 cnfcom.k K = x M dom f + 𝑜 x x dom f M + 𝑜 x -1
10 cnfcom.w W = G dom G
11 cnfcom3.1 φ ω B
12 cnfcom.x X = u F W , v ω 𝑜 W F W 𝑜 v + 𝑜 u
13 cnfcom.y Y = u F W , v ω 𝑜 W ω 𝑜 W 𝑜 u + 𝑜 v
14 cnfcom.n N = X Y -1 T dom G
15 omelon ω On
16 suppssdm F supp dom F
17 15 a1i φ ω On
18 1 17 2 cantnff1o φ ω CNF A : S 1-1 onto ω 𝑜 A
19 f1ocnv ω CNF A : S 1-1 onto ω 𝑜 A ω CNF A -1 : ω 𝑜 A 1-1 onto S
20 f1of ω CNF A -1 : ω 𝑜 A 1-1 onto S ω CNF A -1 : ω 𝑜 A S
21 18 19 20 3syl φ ω CNF A -1 : ω 𝑜 A S
22 21 3 ffvelrnd φ ω CNF A -1 B S
23 4 22 eqeltrid φ F S
24 1 17 2 cantnfs φ F S F : A ω finSupp F
25 23 24 mpbid φ F : A ω finSupp F
26 25 simpld φ F : A ω
27 16 26 fssdm φ F supp A
28 ovex F supp V
29 5 oion F supp V dom G On
30 28 29 ax-mp dom G On
31 30 elexi dom G V
32 31 uniex dom G V
33 32 sucid dom G suc dom G
34 peano1 ω
35 34 a1i φ ω
36 11 35 sseldd φ B
37 1 2 3 4 5 6 7 8 9 10 36 cnfcom2lem φ dom G = suc dom G
38 33 37 eleqtrrid φ dom G dom G
39 5 oif G : dom G F supp
40 39 ffvelrni dom G dom G G dom G supp F
41 38 40 syl φ G dom G supp F
42 10 41 eqeltrid φ W supp F
43 27 42 sseldd φ W A
44 onelon A On W A W On
45 2 43 44 syl2anc φ W On
46 oecl ω On W On ω 𝑜 W On
47 15 45 46 sylancr φ ω 𝑜 W On
48 26 43 ffvelrnd φ F W ω
49 nnon F W ω F W On
50 48 49 syl φ F W On
51 13 12 omf1o ω 𝑜 W On F W On X Y -1 : ω 𝑜 W 𝑜 F W 1-1 onto F W 𝑜 ω 𝑜 W
52 47 50 51 syl2anc φ X Y -1 : ω 𝑜 W 𝑜 F W 1-1 onto F W 𝑜 ω 𝑜 W
53 26 ffnd φ F Fn A
54 0ex V
55 54 a1i φ V
56 elsuppfn F Fn A A On V W supp F W A F W
57 53 2 55 56 syl3anc φ W supp F W A F W
58 simpr W A F W F W
59 57 58 syl6bi φ W supp F F W
60 42 59 mpd φ F W
61 on0eln0 F W On F W F W
62 48 49 61 3syl φ F W F W
63 60 62 mpbird φ F W
64 1 2 3 4 5 6 7 8 9 10 11 cnfcom3lem φ W On 1 𝑜
65 ondif1 W On 1 𝑜 W On W
66 65 simprbi W On 1 𝑜 W
67 64 66 syl φ W
68 omabs F W ω F W W On W F W 𝑜 ω 𝑜 W = ω 𝑜 W
69 48 63 45 67 68 syl22anc φ F W 𝑜 ω 𝑜 W = ω 𝑜 W
70 69 f1oeq3d φ X Y -1 : ω 𝑜 W 𝑜 F W 1-1 onto F W 𝑜 ω 𝑜 W X Y -1 : ω 𝑜 W 𝑜 F W 1-1 onto ω 𝑜 W
71 52 70 mpbid φ X Y -1 : ω 𝑜 W 𝑜 F W 1-1 onto ω 𝑜 W
72 1 2 3 4 5 6 7 8 9 10 36 cnfcom2 φ T dom G : B 1-1 onto ω 𝑜 W 𝑜 F W
73 f1oco X Y -1 : ω 𝑜 W 𝑜 F W 1-1 onto ω 𝑜 W T dom G : B 1-1 onto ω 𝑜 W 𝑜 F W X Y -1 T dom G : B 1-1 onto ω 𝑜 W
74 71 72 73 syl2anc φ X Y -1 T dom G : B 1-1 onto ω 𝑜 W
75 f1oeq1 N = X Y -1 T dom G N : B 1-1 onto ω 𝑜 W X Y -1 T dom G : B 1-1 onto ω 𝑜 W
76 14 75 ax-mp N : B 1-1 onto ω 𝑜 W X Y -1 T dom G : B 1-1 onto ω 𝑜 W
77 74 76 sylibr φ N : B 1-1 onto ω 𝑜 W