| Step | Hyp | Ref
 | Expression | 
| 1 |   | mulgval.b | 
. . . 4
⊢ 𝐵 = (Base‘𝐺) | 
| 2 | 1 | basmex 12737 | 
. . 3
⊢ (𝑋 ∈ 𝐵 → 𝐺 ∈ V) | 
| 3 | 2 | adantl 277 | 
. 2
⊢ ((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) → 𝐺 ∈ V) | 
| 4 |   | mulgval.p | 
. . . . 5
⊢  + =
(+g‘𝐺) | 
| 5 |   | mulgval.o | 
. . . . 5
⊢  0 =
(0g‘𝐺) | 
| 6 |   | mulgval.i | 
. . . . 5
⊢ 𝐼 = (invg‘𝐺) | 
| 7 |   | mulgval.t | 
. . . . 5
⊢  · =
(.g‘𝐺) | 
| 8 | 1, 4, 5, 6, 7 | mulgfvalg 13251 | 
. . . 4
⊢ (𝐺 ∈ V → · =
(𝑛 ∈ ℤ, 𝑥 ∈ 𝐵 ↦ if(𝑛 = 0, 0 , if(0 < 𝑛, (seq1( + , (ℕ × {𝑥}))‘𝑛), (𝐼‘(seq1( + , (ℕ × {𝑥}))‘-𝑛)))))) | 
| 9 | 8 | adantl 277 | 
. . 3
⊢ (((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) → · = (𝑛 ∈ ℤ, 𝑥 ∈ 𝐵 ↦ if(𝑛 = 0, 0 , if(0 < 𝑛, (seq1( + , (ℕ × {𝑥}))‘𝑛), (𝐼‘(seq1( + , (ℕ × {𝑥}))‘-𝑛)))))) | 
| 10 |   | simpl 109 | 
. . . . . 6
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → 𝑛 = 𝑁) | 
| 11 | 10 | eqeq1d 2205 | 
. . . . 5
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → (𝑛 = 0 ↔ 𝑁 = 0)) | 
| 12 | 10 | breq2d 4045 | 
. . . . . 6
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → (0 < 𝑛 ↔ 0 < 𝑁)) | 
| 13 |   | simpr 110 | 
. . . . . . . . . . 11
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → 𝑥 = 𝑋) | 
| 14 | 13 | sneqd 3635 | 
. . . . . . . . . 10
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → {𝑥} = {𝑋}) | 
| 15 | 14 | xpeq2d 4687 | 
. . . . . . . . 9
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → (ℕ × {𝑥}) = (ℕ × {𝑋})) | 
| 16 | 15 | seqeq3d 10547 | 
. . . . . . . 8
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → seq1( + , (ℕ × {𝑥})) = seq1( + , (ℕ × {𝑋}))) | 
| 17 |   | mulgval.s | 
. . . . . . . 8
⊢ 𝑆 = seq1( + , (ℕ × {𝑋})) | 
| 18 | 16, 17 | eqtr4di 2247 | 
. . . . . . 7
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → seq1( + , (ℕ × {𝑥})) = 𝑆) | 
| 19 | 18, 10 | fveq12d 5565 | 
. . . . . 6
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → (seq1( + , (ℕ × {𝑥}))‘𝑛) = (𝑆‘𝑁)) | 
| 20 | 10 | negeqd 8221 | 
. . . . . . . 8
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → -𝑛 = -𝑁) | 
| 21 | 18, 20 | fveq12d 5565 | 
. . . . . . 7
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → (seq1( + , (ℕ × {𝑥}))‘-𝑛) = (𝑆‘-𝑁)) | 
| 22 | 21 | fveq2d 5562 | 
. . . . . 6
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → (𝐼‘(seq1( + , (ℕ × {𝑥}))‘-𝑛)) = (𝐼‘(𝑆‘-𝑁))) | 
| 23 | 12, 19, 22 | ifbieq12d 3587 | 
. . . . 5
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → if(0 < 𝑛, (seq1( + , (ℕ × {𝑥}))‘𝑛), (𝐼‘(seq1( + , (ℕ × {𝑥}))‘-𝑛))) = if(0 < 𝑁, (𝑆‘𝑁), (𝐼‘(𝑆‘-𝑁)))) | 
| 24 | 11, 23 | ifbieq2d 3585 | 
. . . 4
⊢ ((𝑛 = 𝑁 ∧ 𝑥 = 𝑋) → if(𝑛 = 0, 0 , if(0 < 𝑛, (seq1( + , (ℕ × {𝑥}))‘𝑛), (𝐼‘(seq1( + , (ℕ × {𝑥}))‘-𝑛)))) = if(𝑁 = 0, 0 , if(0 < 𝑁, (𝑆‘𝑁), (𝐼‘(𝑆‘-𝑁))))) | 
| 25 | 24 | adantl 277 | 
. . 3
⊢ ((((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) ∧ (𝑛 = 𝑁 ∧ 𝑥 = 𝑋)) → if(𝑛 = 0, 0 , if(0 < 𝑛, (seq1( + , (ℕ × {𝑥}))‘𝑛), (𝐼‘(seq1( + , (ℕ × {𝑥}))‘-𝑛)))) = if(𝑁 = 0, 0 , if(0 < 𝑁, (𝑆‘𝑁), (𝐼‘(𝑆‘-𝑁))))) | 
| 26 |   | simpll 527 | 
. . 3
⊢ (((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) → 𝑁 ∈ ℤ) | 
| 27 |   | simplr 528 | 
. . 3
⊢ (((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) → 𝑋 ∈ 𝐵) | 
| 28 |   | fn0g 13018 | 
. . . . . . 7
⊢
0g Fn V | 
| 29 |   | funfvex 5575 | 
. . . . . . . 8
⊢ ((Fun
0g ∧ 𝐺
∈ dom 0g) → (0g‘𝐺) ∈ V) | 
| 30 | 29 | funfni 5358 | 
. . . . . . 7
⊢
((0g Fn V ∧ 𝐺 ∈ V) → (0g‘𝐺) ∈ V) | 
| 31 | 28, 30 | mpan 424 | 
. . . . . 6
⊢ (𝐺 ∈ V →
(0g‘𝐺)
∈ V) | 
| 32 | 5, 31 | eqeltrid 2283 | 
. . . . 5
⊢ (𝐺 ∈ V → 0 ∈
V) | 
| 33 | 32 | ad2antlr 489 | 
. . . 4
⊢ ((((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) ∧ 𝑁 = 0) → 0 ∈ V) | 
| 34 |   | nnuz 9637 | 
. . . . . . . . 9
⊢ ℕ =
(ℤ≥‘1) | 
| 35 |   | 1zzd 9353 | 
. . . . . . . . 9
⊢ ((𝑋 ∈ 𝐵 ∧ 𝐺 ∈ V) → 1 ∈
ℤ) | 
| 36 |   | fvconst2g 5776 | 
. . . . . . . . . . . 12
⊢ ((𝑋 ∈ 𝐵 ∧ 𝑢 ∈ ℕ) → ((ℕ ×
{𝑋})‘𝑢) = 𝑋) | 
| 37 |   | simpl 109 | 
. . . . . . . . . . . 12
⊢ ((𝑋 ∈ 𝐵 ∧ 𝑢 ∈ ℕ) → 𝑋 ∈ 𝐵) | 
| 38 | 36, 37 | eqeltrd 2273 | 
. . . . . . . . . . 11
⊢ ((𝑋 ∈ 𝐵 ∧ 𝑢 ∈ ℕ) → ((ℕ ×
{𝑋})‘𝑢) ∈ 𝐵) | 
| 39 | 38 | elexd 2776 | 
. . . . . . . . . 10
⊢ ((𝑋 ∈ 𝐵 ∧ 𝑢 ∈ ℕ) → ((ℕ ×
{𝑋})‘𝑢) ∈ V) | 
| 40 | 39 | adantlr 477 | 
. . . . . . . . 9
⊢ (((𝑋 ∈ 𝐵 ∧ 𝐺 ∈ V) ∧ 𝑢 ∈ ℕ) → ((ℕ ×
{𝑋})‘𝑢) ∈ V) | 
| 41 |   | simprl 529 | 
. . . . . . . . . 10
⊢ (((𝑋 ∈ 𝐵 ∧ 𝐺 ∈ V) ∧ (𝑢 ∈ V ∧ 𝑣 ∈ V)) → 𝑢 ∈ V) | 
| 42 |   | plusgslid 12790 | 
. . . . . . . . . . . . 13
⊢
(+g = Slot (+g‘ndx) ∧
(+g‘ndx) ∈ ℕ) | 
| 43 | 42 | slotex 12705 | 
. . . . . . . . . . . 12
⊢ (𝐺 ∈ V →
(+g‘𝐺)
∈ V) | 
| 44 | 4, 43 | eqeltrid 2283 | 
. . . . . . . . . . 11
⊢ (𝐺 ∈ V → + ∈
V) | 
| 45 | 44 | ad2antlr 489 | 
. . . . . . . . . 10
⊢ (((𝑋 ∈ 𝐵 ∧ 𝐺 ∈ V) ∧ (𝑢 ∈ V ∧ 𝑣 ∈ V)) → + ∈ V) | 
| 46 |   | simprr 531 | 
. . . . . . . . . 10
⊢ (((𝑋 ∈ 𝐵 ∧ 𝐺 ∈ V) ∧ (𝑢 ∈ V ∧ 𝑣 ∈ V)) → 𝑣 ∈ V) | 
| 47 |   | ovexg 5956 | 
. . . . . . . . . 10
⊢ ((𝑢 ∈ V ∧ + ∈ V
∧ 𝑣 ∈ V) →
(𝑢 + 𝑣) ∈ V) | 
| 48 | 41, 45, 46, 47 | syl3anc 1249 | 
. . . . . . . . 9
⊢ (((𝑋 ∈ 𝐵 ∧ 𝐺 ∈ V) ∧ (𝑢 ∈ V ∧ 𝑣 ∈ V)) → (𝑢 + 𝑣) ∈ V) | 
| 49 | 34, 35, 40, 48 | seqf 10556 | 
. . . . . . . 8
⊢ ((𝑋 ∈ 𝐵 ∧ 𝐺 ∈ V) → seq1( + , (ℕ × {𝑋})):ℕ⟶V) | 
| 50 | 17 | feq1i 5400 | 
. . . . . . . 8
⊢ (𝑆:ℕ⟶V ↔ seq1(
+ ,
(ℕ × {𝑋})):ℕ⟶V) | 
| 51 | 49, 50 | sylibr 134 | 
. . . . . . 7
⊢ ((𝑋 ∈ 𝐵 ∧ 𝐺 ∈ V) → 𝑆:ℕ⟶V) | 
| 52 | 51 | ad5ant23 522 | 
. . . . . 6
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ 0 < 𝑁) → 𝑆:ℕ⟶V) | 
| 53 |   | simp-4l 541 | 
. . . . . . 7
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ 0 < 𝑁) → 𝑁 ∈ ℤ) | 
| 54 |   | simpr 110 | 
. . . . . . 7
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ 0 < 𝑁) → 0 < 𝑁) | 
| 55 |   | elnnz 9336 | 
. . . . . . 7
⊢ (𝑁 ∈ ℕ ↔ (𝑁 ∈ ℤ ∧ 0 <
𝑁)) | 
| 56 | 53, 54, 55 | sylanbrc 417 | 
. . . . . 6
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ 0 < 𝑁) → 𝑁 ∈ ℕ) | 
| 57 | 52, 56 | ffvelcdmd 5698 | 
. . . . 5
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ 0 < 𝑁) → (𝑆‘𝑁) ∈ V) | 
| 58 | 1, 6 | grpinvfng 13176 | 
. . . . . . . 8
⊢ (𝐺 ∈ V → 𝐼 Fn 𝐵) | 
| 59 |   | basfn 12736 | 
. . . . . . . . . 10
⊢ Base Fn
V | 
| 60 |   | funfvex 5575 | 
. . . . . . . . . . 11
⊢ ((Fun
Base ∧ 𝐺 ∈ dom
Base) → (Base‘𝐺)
∈ V) | 
| 61 | 60 | funfni 5358 | 
. . . . . . . . . 10
⊢ ((Base Fn
V ∧ 𝐺 ∈ V) →
(Base‘𝐺) ∈
V) | 
| 62 | 59, 61 | mpan 424 | 
. . . . . . . . 9
⊢ (𝐺 ∈ V →
(Base‘𝐺) ∈
V) | 
| 63 | 1, 62 | eqeltrid 2283 | 
. . . . . . . 8
⊢ (𝐺 ∈ V → 𝐵 ∈ V) | 
| 64 |   | fnex 5784 | 
. . . . . . . 8
⊢ ((𝐼 Fn 𝐵 ∧ 𝐵 ∈ V) → 𝐼 ∈ V) | 
| 65 | 58, 63, 64 | syl2anc 411 | 
. . . . . . 7
⊢ (𝐺 ∈ V → 𝐼 ∈ V) | 
| 66 | 65 | ad3antlr 493 | 
. . . . . 6
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → 𝐼 ∈ V) | 
| 67 | 51 | ad5ant23 522 | 
. . . . . . 7
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → 𝑆:ℕ⟶V) | 
| 68 |   | znegcl 9357 | 
. . . . . . . . 9
⊢ (𝑁 ∈ ℤ → -𝑁 ∈
ℤ) | 
| 69 | 68 | ad4antr 494 | 
. . . . . . . 8
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → -𝑁 ∈ ℤ) | 
| 70 |   | simplr 528 | 
. . . . . . . . . 10
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → ¬ 𝑁 = 0) | 
| 71 |   | simpr 110 | 
. . . . . . . . . 10
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → ¬ 0 < 𝑁) | 
| 72 |   | ztri3or0 9368 | 
. . . . . . . . . . 11
⊢ (𝑁 ∈ ℤ → (𝑁 < 0 ∨ 𝑁 = 0 ∨ 0 < 𝑁)) | 
| 73 | 72 | ad4antr 494 | 
. . . . . . . . . 10
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → (𝑁 < 0 ∨ 𝑁 = 0 ∨ 0 < 𝑁)) | 
| 74 | 70, 71, 73 | ecase23d 1361 | 
. . . . . . . . 9
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → 𝑁 < 0) | 
| 75 |   | zre 9330 | 
. . . . . . . . . . 11
⊢ (𝑁 ∈ ℤ → 𝑁 ∈
ℝ) | 
| 76 | 75 | ad4antr 494 | 
. . . . . . . . . 10
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → 𝑁 ∈ ℝ) | 
| 77 | 76 | lt0neg1d 8542 | 
. . . . . . . . 9
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → (𝑁 < 0 ↔ 0 < -𝑁)) | 
| 78 | 74, 77 | mpbid 147 | 
. . . . . . . 8
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → 0 < -𝑁) | 
| 79 |   | elnnz 9336 | 
. . . . . . . 8
⊢ (-𝑁 ∈ ℕ ↔ (-𝑁 ∈ ℤ ∧ 0 <
-𝑁)) | 
| 80 | 69, 78, 79 | sylanbrc 417 | 
. . . . . . 7
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → -𝑁 ∈ ℕ) | 
| 81 | 67, 80 | ffvelcdmd 5698 | 
. . . . . 6
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → (𝑆‘-𝑁) ∈ V) | 
| 82 |   | fvexg 5577 | 
. . . . . 6
⊢ ((𝐼 ∈ V ∧ (𝑆‘-𝑁) ∈ V) → (𝐼‘(𝑆‘-𝑁)) ∈ V) | 
| 83 | 66, 81, 82 | syl2anc 411 | 
. . . . 5
⊢
(((((𝑁 ∈
ℤ ∧ 𝑋 ∈
𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) ∧ ¬ 0 < 𝑁) → (𝐼‘(𝑆‘-𝑁)) ∈ V) | 
| 84 |   | 0zd 9338 | 
. . . . . 6
⊢ ((((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) → 0 ∈
ℤ) | 
| 85 |   | simplll 533 | 
. . . . . 6
⊢ ((((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) → 𝑁 ∈ ℤ) | 
| 86 |   | zdclt 9403 | 
. . . . . 6
⊢ ((0
∈ ℤ ∧ 𝑁
∈ ℤ) → DECID 0 < 𝑁) | 
| 87 | 84, 85, 86 | syl2anc 411 | 
. . . . 5
⊢ ((((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) → DECID 0 <
𝑁) | 
| 88 | 57, 83, 87 | ifcldadc 3590 | 
. . . 4
⊢ ((((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) ∧ ¬ 𝑁 = 0) → if(0 < 𝑁, (𝑆‘𝑁), (𝐼‘(𝑆‘-𝑁))) ∈ V) | 
| 89 |   | 0zd 9338 | 
. . . . 5
⊢ (((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) → 0 ∈
ℤ) | 
| 90 |   | zdceq 9401 | 
. . . . 5
⊢ ((𝑁 ∈ ℤ ∧ 0 ∈
ℤ) → DECID 𝑁 = 0) | 
| 91 | 26, 89, 90 | syl2anc 411 | 
. . . 4
⊢ (((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) → DECID 𝑁 = 0) | 
| 92 | 33, 88, 91 | ifcldadc 3590 | 
. . 3
⊢ (((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) → if(𝑁 = 0, 0 , if(0 < 𝑁, (𝑆‘𝑁), (𝐼‘(𝑆‘-𝑁)))) ∈ V) | 
| 93 | 9, 25, 26, 27, 92 | ovmpod 6050 | 
. 2
⊢ (((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) ∧ 𝐺 ∈ V) → (𝑁 · 𝑋) = if(𝑁 = 0, 0 , if(0 < 𝑁, (𝑆‘𝑁), (𝐼‘(𝑆‘-𝑁))))) | 
| 94 | 3, 93 | mpdan 421 | 
1
⊢ ((𝑁 ∈ ℤ ∧ 𝑋 ∈ 𝐵) → (𝑁 · 𝑋) = if(𝑁 = 0, 0 , if(0 < 𝑁, (𝑆‘𝑁), (𝐼‘(𝑆‘-𝑁))))) |