Metamath Proof Explorer


Theorem psrgrp

Description: The ring of power series is a group. (Contributed by Mario Carneiro, 29-Dec-2014) (Proof shortened by SN, 7-Feb-2025)

Ref Expression
Hypotheses psrgrp.s ⊢ S = I mPwSer R
psrgrp.i ⊢ φ → I ∈ V
psrgrp.r ⊢ φ → R ∈ Grp
Assertion psrgrp ⊢ φ → S ∈ Grp

Proof

Step Hyp Ref Expression
1 psrgrp.s ⊢ S = I mPwSer R
2 psrgrp.i ⊢ φ → I ∈ V
3 psrgrp.r ⊢ φ → R ∈ Grp
4 ovex ⊢ ℕ 0 I ∈ V
5 4 rabex ⊢ f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∈ V
6 eqid ⊢ R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin = R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
7 6 pwsgrp ⊢ R ∈ Grp ∧ f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∈ V → R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∈ Grp
8 3 5 7 sylancl ⊢ φ → R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∈ Grp
9 eqid ⊢ Base R = Base R
10 6 9 pwsbas ⊢ R ∈ Grp ∧ f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∈ V → Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin = Base R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
11 3 5 10 sylancl ⊢ φ → Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin = Base R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
12 eqid ⊢ f ∈ ℕ 0 I | f -1 ℕ ∈ Fin = f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
13 eqid ⊢ Base S = Base S
14 1 9 12 13 2 psrbas ⊢ φ → Base S = Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
15 14 eqcomd ⊢ φ → Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin = Base S
16 eqid ⊢ Base R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin = Base R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
17 3 adantr ⊢ φ ∧ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∧ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → R ∈ Grp
18 5 a1i ⊢ φ ∧ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∧ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∈ V
19 11 eleq2d ⊢ φ → x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ↔ x ∈ Base R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
20 19 biimpa ⊢ φ ∧ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → x ∈ Base R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
21 20 adantrr ⊢ φ ∧ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∧ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → x ∈ Base R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
22 11 eleq2d ⊢ φ → y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ↔ y ∈ Base R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
23 22 biimpa ⊢ φ ∧ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → y ∈ Base R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
24 23 adantrl ⊢ φ ∧ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∧ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → y ∈ Base R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
25 eqid ⊢ + R = + R
26 eqid ⊢ + R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin = + R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
27 6 16 17 18 21 24 25 26 pwsplusgval ⊢ φ ∧ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∧ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → x + R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin y = x + R f y
28 eqid ⊢ + S = + S
29 14 eleq2d ⊢ φ → x ∈ Base S ↔ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
30 29 biimpar ⊢ φ ∧ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → x ∈ Base S
31 30 adantrr ⊢ φ ∧ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∧ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → x ∈ Base S
32 14 eleq2d ⊢ φ → y ∈ Base S ↔ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin
33 32 biimpar ⊢ φ ∧ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → y ∈ Base S
34 33 adantrl ⊢ φ ∧ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∧ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → y ∈ Base S
35 1 13 25 28 31 34 psradd ⊢ φ ∧ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∧ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → x + S y = x + R f y
36 27 35 eqtr4d ⊢ φ ∧ x ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∧ y ∈ Base R f ∈ ℕ 0 I | f -1 ℕ ∈ Fin → x + R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin y = x + S y
37 11 15 36 grppropd ⊢ φ → R ↑ 𝑠 f ∈ ℕ 0 I | f -1 ℕ ∈ Fin ∈ Grp ↔ S ∈ Grp
38 8 37 mpbid ⊢ φ → S ∈ Grp