| Step | Hyp | Ref
 | Expression | 
| 1 |   | mullid 8024 | 
. . 3
⊢ (𝑛 ∈ ℂ → (1
· 𝑛) = 𝑛) | 
| 2 | 1 | adantl 277 | 
. 2
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ ℂ) → (1 · 𝑛) = 𝑛) | 
| 3 |   | 1cnd 8042 | 
. 2
⊢ ((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) → 1 ∈
ℂ) | 
| 4 |   | prodrb.3 | 
. . 3
⊢ (𝜑 → 𝑁 ∈ (ℤ≥‘𝑀)) | 
| 5 | 4 | adantr 276 | 
. 2
⊢ ((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) → 𝑁 ∈ (ℤ≥‘𝑀)) | 
| 6 |   | eluzelz 9610 | 
. . . . 5
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → 𝑁 ∈ ℤ) | 
| 7 | 5, 6 | syl 14 | 
. . . 4
⊢ ((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) → 𝑁 ∈ ℤ) | 
| 8 |   | prodrbdc.dc | 
. . . . . . . . 9
⊢ ((𝜑 ∧ 𝑘 ∈ (ℤ≥‘𝑀)) → DECID
𝑘 ∈ 𝐴) | 
| 9 |   | exmiddc 837 | 
. . . . . . . . 9
⊢
(DECID 𝑘 ∈ 𝐴 → (𝑘 ∈ 𝐴 ∨ ¬ 𝑘 ∈ 𝐴)) | 
| 10 | 8, 9 | syl 14 | 
. . . . . . . 8
⊢ ((𝜑 ∧ 𝑘 ∈ (ℤ≥‘𝑀)) → (𝑘 ∈ 𝐴 ∨ ¬ 𝑘 ∈ 𝐴)) | 
| 11 |   | iftrue 3566 | 
. . . . . . . . . . . . 13
⊢ (𝑘 ∈ 𝐴 → if(𝑘 ∈ 𝐴, 𝐵, 1) = 𝐵) | 
| 12 | 11 | adantl 277 | 
. . . . . . . . . . . 12
⊢ ((𝜑 ∧ 𝑘 ∈ 𝐴) → if(𝑘 ∈ 𝐴, 𝐵, 1) = 𝐵) | 
| 13 |   | prodmo.2 | 
. . . . . . . . . . . 12
⊢ ((𝜑 ∧ 𝑘 ∈ 𝐴) → 𝐵 ∈ ℂ) | 
| 14 | 12, 13 | eqeltrd 2273 | 
. . . . . . . . . . 11
⊢ ((𝜑 ∧ 𝑘 ∈ 𝐴) → if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ) | 
| 15 | 14 | ex 115 | 
. . . . . . . . . 10
⊢ (𝜑 → (𝑘 ∈ 𝐴 → if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ)) | 
| 16 |   | iffalse 3569 | 
. . . . . . . . . . . 12
⊢ (¬
𝑘 ∈ 𝐴 → if(𝑘 ∈ 𝐴, 𝐵, 1) = 1) | 
| 17 |   | ax-1cn 7972 | 
. . . . . . . . . . . 12
⊢ 1 ∈
ℂ | 
| 18 | 16, 17 | eqeltrdi 2287 | 
. . . . . . . . . . 11
⊢ (¬
𝑘 ∈ 𝐴 → if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ) | 
| 19 | 18 | a1i 9 | 
. . . . . . . . . 10
⊢ (𝜑 → (¬ 𝑘 ∈ 𝐴 → if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ)) | 
| 20 | 15, 19 | jaod 718 | 
. . . . . . . . 9
⊢ (𝜑 → ((𝑘 ∈ 𝐴 ∨ ¬ 𝑘 ∈ 𝐴) → if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ)) | 
| 21 | 20 | adantr 276 | 
. . . . . . . 8
⊢ ((𝜑 ∧ 𝑘 ∈ (ℤ≥‘𝑀)) → ((𝑘 ∈ 𝐴 ∨ ¬ 𝑘 ∈ 𝐴) → if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ)) | 
| 22 | 10, 21 | mpd 13 | 
. . . . . . 7
⊢ ((𝜑 ∧ 𝑘 ∈ (ℤ≥‘𝑀)) → if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ) | 
| 23 | 22 | ralrimiva 2570 | 
. . . . . 6
⊢ (𝜑 → ∀𝑘 ∈ (ℤ≥‘𝑀)if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ) | 
| 24 |   | nfcv 2339 | 
. . . . . . . . . 10
⊢
Ⅎ𝑘𝑁 | 
| 25 | 24 | nfel1 2350 | 
. . . . . . . . 9
⊢
Ⅎ𝑘 𝑁 ∈ 𝐴 | 
| 26 |   | nfcsb1v 3117 | 
. . . . . . . . 9
⊢
Ⅎ𝑘⦋𝑁 / 𝑘⦌𝐵 | 
| 27 |   | nfcv 2339 | 
. . . . . . . . 9
⊢
Ⅎ𝑘1 | 
| 28 | 25, 26, 27 | nfif 3589 | 
. . . . . . . 8
⊢
Ⅎ𝑘if(𝑁 ∈ 𝐴, ⦋𝑁 / 𝑘⦌𝐵, 1) | 
| 29 | 28 | nfel1 2350 | 
. . . . . . 7
⊢
Ⅎ𝑘if(𝑁 ∈ 𝐴, ⦋𝑁 / 𝑘⦌𝐵, 1) ∈ ℂ | 
| 30 |   | eleq1 2259 | 
. . . . . . . . 9
⊢ (𝑘 = 𝑁 → (𝑘 ∈ 𝐴 ↔ 𝑁 ∈ 𝐴)) | 
| 31 |   | csbeq1a 3093 | 
. . . . . . . . 9
⊢ (𝑘 = 𝑁 → 𝐵 = ⦋𝑁 / 𝑘⦌𝐵) | 
| 32 | 30, 31 | ifbieq1d 3583 | 
. . . . . . . 8
⊢ (𝑘 = 𝑁 → if(𝑘 ∈ 𝐴, 𝐵, 1) = if(𝑁 ∈ 𝐴, ⦋𝑁 / 𝑘⦌𝐵, 1)) | 
| 33 | 32 | eleq1d 2265 | 
. . . . . . 7
⊢ (𝑘 = 𝑁 → (if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ ↔ if(𝑁 ∈ 𝐴, ⦋𝑁 / 𝑘⦌𝐵, 1) ∈ ℂ)) | 
| 34 | 29, 33 | rspc 2862 | 
. . . . . 6
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → (∀𝑘 ∈ (ℤ≥‘𝑀)if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ → if(𝑁 ∈ 𝐴, ⦋𝑁 / 𝑘⦌𝐵, 1) ∈ ℂ)) | 
| 35 | 4, 23, 34 | sylc 62 | 
. . . . 5
⊢ (𝜑 → if(𝑁 ∈ 𝐴, ⦋𝑁 / 𝑘⦌𝐵, 1) ∈ ℂ) | 
| 36 | 35 | adantr 276 | 
. . . 4
⊢ ((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) → if(𝑁 ∈ 𝐴, ⦋𝑁 / 𝑘⦌𝐵, 1) ∈ ℂ) | 
| 37 |   | prodmo.1 | 
. . . . 5
⊢ 𝐹 = (𝑘 ∈ ℤ ↦ if(𝑘 ∈ 𝐴, 𝐵, 1)) | 
| 38 | 24, 28, 32, 37 | fvmptf 5654 | 
. . . 4
⊢ ((𝑁 ∈ ℤ ∧ if(𝑁 ∈ 𝐴, ⦋𝑁 / 𝑘⦌𝐵, 1) ∈ ℂ) → (𝐹‘𝑁) = if(𝑁 ∈ 𝐴, ⦋𝑁 / 𝑘⦌𝐵, 1)) | 
| 39 | 7, 36, 38 | syl2anc 411 | 
. . 3
⊢ ((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) → (𝐹‘𝑁) = if(𝑁 ∈ 𝐴, ⦋𝑁 / 𝑘⦌𝐵, 1)) | 
| 40 | 39, 36 | eqeltrd 2273 | 
. 2
⊢ ((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) → (𝐹‘𝑁) ∈ ℂ) | 
| 41 |   | elfzelz 10100 | 
. . . 4
⊢ (𝑛 ∈ (𝑀...(𝑁 − 1)) → 𝑛 ∈ ℤ) | 
| 42 |   | elfzuz 10096 | 
. . . . . 6
⊢ (𝑛 ∈ (𝑀...(𝑁 − 1)) → 𝑛 ∈ (ℤ≥‘𝑀)) | 
| 43 | 42 | adantl 277 | 
. . . . 5
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (𝑀...(𝑁 − 1))) → 𝑛 ∈ (ℤ≥‘𝑀)) | 
| 44 | 23 | ad2antrr 488 | 
. . . . 5
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (𝑀...(𝑁 − 1))) → ∀𝑘 ∈
(ℤ≥‘𝑀)if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ) | 
| 45 |   | nfv 1542 | 
. . . . . . . 8
⊢
Ⅎ𝑘 𝑛 ∈ 𝐴 | 
| 46 |   | nfcsb1v 3117 | 
. . . . . . . 8
⊢
Ⅎ𝑘⦋𝑛 / 𝑘⦌𝐵 | 
| 47 | 45, 46, 27 | nfif 3589 | 
. . . . . . 7
⊢
Ⅎ𝑘if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1) | 
| 48 | 47 | nfel1 2350 | 
. . . . . 6
⊢
Ⅎ𝑘if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1) ∈ ℂ | 
| 49 |   | eleq1w 2257 | 
. . . . . . . 8
⊢ (𝑘 = 𝑛 → (𝑘 ∈ 𝐴 ↔ 𝑛 ∈ 𝐴)) | 
| 50 |   | csbeq1a 3093 | 
. . . . . . . 8
⊢ (𝑘 = 𝑛 → 𝐵 = ⦋𝑛 / 𝑘⦌𝐵) | 
| 51 | 49, 50 | ifbieq1d 3583 | 
. . . . . . 7
⊢ (𝑘 = 𝑛 → if(𝑘 ∈ 𝐴, 𝐵, 1) = if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1)) | 
| 52 | 51 | eleq1d 2265 | 
. . . . . 6
⊢ (𝑘 = 𝑛 → (if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ ↔ if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1) ∈ ℂ)) | 
| 53 | 48, 52 | rspc 2862 | 
. . . . 5
⊢ (𝑛 ∈
(ℤ≥‘𝑀) → (∀𝑘 ∈ (ℤ≥‘𝑀)if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ → if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1) ∈ ℂ)) | 
| 54 | 43, 44, 53 | sylc 62 | 
. . . 4
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (𝑀...(𝑁 − 1))) → if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1) ∈ ℂ) | 
| 55 |   | nfcv 2339 | 
. . . . 5
⊢
Ⅎ𝑘𝑛 | 
| 56 | 55, 47, 51, 37 | fvmptf 5654 | 
. . . 4
⊢ ((𝑛 ∈ ℤ ∧ if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1) ∈ ℂ) → (𝐹‘𝑛) = if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1)) | 
| 57 | 41, 54, 56 | syl2an2 594 | 
. . 3
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (𝑀...(𝑁 − 1))) → (𝐹‘𝑛) = if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1)) | 
| 58 |   | uznfz 10178 | 
. . . . . . 7
⊢ (𝑛 ∈
(ℤ≥‘𝑁) → ¬ 𝑛 ∈ (𝑀...(𝑁 − 1))) | 
| 59 | 58 | con2i 628 | 
. . . . . 6
⊢ (𝑛 ∈ (𝑀...(𝑁 − 1)) → ¬ 𝑛 ∈ (ℤ≥‘𝑁)) | 
| 60 | 59 | adantl 277 | 
. . . . 5
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (𝑀...(𝑁 − 1))) → ¬ 𝑛 ∈
(ℤ≥‘𝑁)) | 
| 61 |   | ssel 3177 | 
. . . . . 6
⊢ (𝐴 ⊆
(ℤ≥‘𝑁) → (𝑛 ∈ 𝐴 → 𝑛 ∈ (ℤ≥‘𝑁))) | 
| 62 | 61 | ad2antlr 489 | 
. . . . 5
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (𝑀...(𝑁 − 1))) → (𝑛 ∈ 𝐴 → 𝑛 ∈ (ℤ≥‘𝑁))) | 
| 63 | 60, 62 | mtod 664 | 
. . . 4
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (𝑀...(𝑁 − 1))) → ¬ 𝑛 ∈ 𝐴) | 
| 64 | 63 | iffalsed 3571 | 
. . 3
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (𝑀...(𝑁 − 1))) → if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1) = 1) | 
| 65 | 57, 64 | eqtrd 2229 | 
. 2
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (𝑀...(𝑁 − 1))) → (𝐹‘𝑛) = 1) | 
| 66 |   | eluzelz 9610 | 
. . . 4
⊢ (𝑛 ∈
(ℤ≥‘𝑀) → 𝑛 ∈ ℤ) | 
| 67 |   | simpr 110 | 
. . . . 5
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (ℤ≥‘𝑀)) → 𝑛 ∈ (ℤ≥‘𝑀)) | 
| 68 | 23 | ad2antrr 488 | 
. . . . 5
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (ℤ≥‘𝑀)) → ∀𝑘 ∈
(ℤ≥‘𝑀)if(𝑘 ∈ 𝐴, 𝐵, 1) ∈ ℂ) | 
| 69 | 67, 68, 53 | sylc 62 | 
. . . 4
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (ℤ≥‘𝑀)) → if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1) ∈ ℂ) | 
| 70 | 66, 69, 56 | syl2an2 594 | 
. . 3
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (ℤ≥‘𝑀)) → (𝐹‘𝑛) = if(𝑛 ∈ 𝐴, ⦋𝑛 / 𝑘⦌𝐵, 1)) | 
| 71 | 70, 69 | eqeltrd 2273 | 
. 2
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ 𝑛 ∈ (ℤ≥‘𝑀)) → (𝐹‘𝑛) ∈ ℂ) | 
| 72 |   | mulcl 8006 | 
. . 3
⊢ ((𝑛 ∈ ℂ ∧ 𝑧 ∈ ℂ) → (𝑛 · 𝑧) ∈ ℂ) | 
| 73 | 72 | adantl 277 | 
. 2
⊢ (((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) ∧ (𝑛 ∈ ℂ ∧ 𝑧 ∈ ℂ)) → (𝑛 · 𝑧) ∈ ℂ) | 
| 74 | 2, 3, 5, 40, 65, 71, 73 | seq3id 10617 | 
1
⊢ ((𝜑 ∧ 𝐴 ⊆ (ℤ≥‘𝑁)) → (seq𝑀( · , 𝐹) ↾
(ℤ≥‘𝑁)) = seq𝑁( · , 𝐹)) |