Metamath Proof Explorer


Theorem sylow3lem4

Description: Lemma for sylow3 , first part. The number of Sylow subgroups is a divisor of the size of G reduced by the size of a Sylow subgroup of G . (Contributed by Mario Carneiro, 19-Jan-2015)

Ref Expression
Hypotheses sylow3.x ⊢ X = Base G
sylow3.g ⊢ φ → G ∈ Grp
sylow3.xf ⊢ φ → X ∈ Fin
sylow3.p ⊢ φ → P ∈ ℙ
sylow3lem1.a ⊢ + ˙ = + G
sylow3lem1.d ⊢ - ˙ = - G
sylow3lem1.m ⊢ ⊕ ˙ = x ∈ X , y ∈ P pSyl G ⟼ ran ⁡ z ∈ y ⟼ x + ˙ z - ˙ x
sylow3lem2.k ⊢ φ → K ∈ P pSyl G
sylow3lem2.h ⊢ H = u ∈ X | u ⊕ ˙ K = K
sylow3lem2.n ⊢ N = x ∈ X | ∀ y ∈ X x + ˙ y ∈ K ↔ y + ˙ x ∈ K
Assertion sylow3lem4 ⊢ φ → P pSyl G ∥ X P P pCnt X

Proof

Step Hyp Ref Expression
1 sylow3.x ⊢ X = Base G
2 sylow3.g ⊢ φ → G ∈ Grp
3 sylow3.xf ⊢ φ → X ∈ Fin
4 sylow3.p ⊢ φ → P ∈ ℙ
5 sylow3lem1.a ⊢ + ˙ = + G
6 sylow3lem1.d ⊢ - ˙ = - G
7 sylow3lem1.m ⊢ ⊕ ˙ = x ∈ X , y ∈ P pSyl G ⟼ ran ⁡ z ∈ y ⟼ x + ˙ z - ˙ x
8 sylow3lem2.k ⊢ φ → K ∈ P pSyl G
9 sylow3lem2.h ⊢ H = u ∈ X | u ⊕ ˙ K = K
10 sylow3lem2.n ⊢ N = x ∈ X | ∀ y ∈ X x + ˙ y ∈ K ↔ y + ˙ x ∈ K
11 1 2 3 4 5 6 7 8 9 10 sylow3lem3 ⊢ φ → P pSyl G = X / G ~ QG N
12 slwsubg ⊢ K ∈ P pSyl G → K ∈ SubGrp ⁡ G
13 8 12 syl ⊢ φ → K ∈ SubGrp ⁡ G
14 eqid ⊢ G ↾ 𝑠 N = G ↾ 𝑠 N
15 10 1 5 14 nmznsg ⊢ K ∈ SubGrp ⁡ G → K ∈ NrmSGrp ⁡ G ↾ 𝑠 N
16 nsgsubg ⊢ K ∈ NrmSGrp ⁡ G ↾ 𝑠 N → K ∈ SubGrp ⁡ G ↾ 𝑠 N
17 15 16 syl ⊢ K ∈ SubGrp ⁡ G → K ∈ SubGrp ⁡ G ↾ 𝑠 N
18 13 17 syl ⊢ φ → K ∈ SubGrp ⁡ G ↾ 𝑠 N
19 10 1 5 nmzsubg ⊢ G ∈ Grp → N ∈ SubGrp ⁡ G
20 2 19 syl ⊢ φ → N ∈ SubGrp ⁡ G
21 14 subgbas ⊢ N ∈ SubGrp ⁡ G → N = Base G ↾ 𝑠 N
22 20 21 syl ⊢ φ → N = Base G ↾ 𝑠 N
23 1 subgss ⊢ N ∈ SubGrp ⁡ G → N ⊆ X
24 20 23 syl ⊢ φ → N ⊆ X
25 3 24 ssfid ⊢ φ → N ∈ Fin
26 22 25 eqeltrrd ⊢ φ → Base G ↾ 𝑠 N ∈ Fin
27 eqid ⊢ Base G ↾ 𝑠 N = Base G ↾ 𝑠 N
28 27 lagsubg ⊢ K ∈ SubGrp ⁡ G ↾ 𝑠 N ∧ Base G ↾ 𝑠 N ∈ Fin → K ∥ Base G ↾ 𝑠 N
29 18 26 28 syl2anc ⊢ φ → K ∥ Base G ↾ 𝑠 N
30 22 fveq2d ⊢ φ → N = Base G ↾ 𝑠 N
31 29 30 breqtrrd ⊢ φ → K ∥ N
32 eqid ⊢ 0 G = 0 G
33 32 subg0cl ⊢ K ∈ SubGrp ⁡ G → 0 G ∈ K
34 13 33 syl ⊢ φ → 0 G ∈ K
35 34 ne0d ⊢ φ → K ≠ ∅
36 1 subgss ⊢ K ∈ SubGrp ⁡ G → K ⊆ X
37 13 36 syl ⊢ φ → K ⊆ X
38 3 37 ssfid ⊢ φ → K ∈ Fin
39 hashnncl ⊢ K ∈ Fin → K ∈ ℕ ↔ K ≠ ∅
40 38 39 syl ⊢ φ → K ∈ ℕ ↔ K ≠ ∅
41 35 40 mpbird ⊢ φ → K ∈ ℕ
42 41 nnzd ⊢ φ → K ∈ ℤ
43 hashcl ⊢ N ∈ Fin → N ∈ ℕ 0
44 25 43 syl ⊢ φ → N ∈ ℕ 0
45 44 nn0zd ⊢ φ → N ∈ ℤ
46 pwfi ⊢ X ∈ Fin ↔ 𝒫 X ∈ Fin
47 3 46 sylib ⊢ φ → 𝒫 X ∈ Fin
48 eqid ⊢ G ~ QG N = G ~ QG N
49 1 48 eqger ⊢ N ∈ SubGrp ⁡ G → G ~ QG N Er X
50 20 49 syl ⊢ φ → G ~ QG N Er X
51 50 qsss ⊢ φ → X / G ~ QG N ⊆ 𝒫 X
52 47 51 ssfid ⊢ φ → X / G ~ QG N ∈ Fin
53 hashcl ⊢ X / G ~ QG N ∈ Fin → X / G ~ QG N ∈ ℕ 0
54 52 53 syl ⊢ φ → X / G ~ QG N ∈ ℕ 0
55 54 nn0zd ⊢ φ → X / G ~ QG N ∈ ℤ
56 dvdscmul ⊢ K ∈ ℤ ∧ N ∈ ℤ ∧ X / G ~ QG N ∈ ℤ → K ∥ N → X / G ~ QG N ⁢ K ∥ X / G ~ QG N ⁢ N
57 42 45 55 56 syl3anc ⊢ φ → K ∥ N → X / G ~ QG N ⁢ K ∥ X / G ~ QG N ⁢ N
58 31 57 mpd ⊢ φ → X / G ~ QG N ⁢ K ∥ X / G ~ QG N ⁢ N
59 hashcl ⊢ X ∈ Fin → X ∈ ℕ 0
60 3 59 syl ⊢ φ → X ∈ ℕ 0
61 60 nn0cnd ⊢ φ → X ∈ ℂ
62 41 nncnd ⊢ φ → K ∈ ℂ
63 41 nnne0d ⊢ φ → K ≠ 0
64 61 62 63 divcan1d ⊢ φ → X K ⁢ K = X
65 1 48 20 3 lagsubg2 ⊢ φ → X = X / G ~ QG N ⁢ N
66 64 65 eqtrd ⊢ φ → X K ⁢ K = X / G ~ QG N ⁢ N
67 58 66 breqtrrd ⊢ φ → X / G ~ QG N ⁢ K ∥ X K ⁢ K
68 1 lagsubg ⊢ K ∈ SubGrp ⁡ G ∧ X ∈ Fin → K ∥ X
69 13 3 68 syl2anc ⊢ φ → K ∥ X
70 60 nn0zd ⊢ φ → X ∈ ℤ
71 dvdsval2 ⊢ K ∈ ℤ ∧ K ≠ 0 ∧ X ∈ ℤ → K ∥ X ↔ X K ∈ ℤ
72 42 63 70 71 syl3anc ⊢ φ → K ∥ X ↔ X K ∈ ℤ
73 69 72 mpbid ⊢ φ → X K ∈ ℤ
74 dvdsmulcr ⊢ X / G ~ QG N ∈ ℤ ∧ X K ∈ ℤ ∧ K ∈ ℤ ∧ K ≠ 0 → X / G ~ QG N ⁢ K ∥ X K ⁢ K ↔ X / G ~ QG N ∥ X K
75 55 73 42 63 74 syl112anc ⊢ φ → X / G ~ QG N ⁢ K ∥ X K ⁢ K ↔ X / G ~ QG N ∥ X K
76 67 75 mpbid ⊢ φ → X / G ~ QG N ∥ X K
77 1 3 8 slwhash ⊢ φ → K = P P pCnt X
78 77 oveq2d ⊢ φ → X K = X P P pCnt X
79 76 78 breqtrd ⊢ φ → X / G ~ QG N ∥ X P P pCnt X
80 11 79 eqbrtrd ⊢ φ → P pSyl G ∥ X P P pCnt X