| Step | Hyp | Ref
 | Expression | 
| 1 |   | nfcv 2339 | 
. . . . 5
⊢
Ⅎ𝑚𝐴 | 
| 2 |   | nfcsb1v 3117 | 
. . . . 5
⊢
Ⅎ𝑘⦋𝑚 / 𝑘⦌𝐴 | 
| 3 |   | csbeq1a 3093 | 
. . . . 5
⊢ (𝑘 = 𝑚 → 𝐴 = ⦋𝑚 / 𝑘⦌𝐴) | 
| 4 | 1, 2, 3 | cbvsumi 11527 | 
. . . 4
⊢
Σ𝑘 ∈
{𝑀}𝐴 = Σ𝑚 ∈ {𝑀}⦋𝑚 / 𝑘⦌𝐴 | 
| 5 |   | csbeq1 3087 | 
. . . . 5
⊢ (𝑚 = ({〈1, 𝑀〉}‘𝑛) → ⦋𝑚 / 𝑘⦌𝐴 = ⦋({〈1, 𝑀〉}‘𝑛) / 𝑘⦌𝐴) | 
| 6 |   | 1nn 9001 | 
. . . . . 6
⊢ 1 ∈
ℕ | 
| 7 | 6 | a1i 9 | 
. . . . 5
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → 1 ∈
ℕ) | 
| 8 |   | simpl 109 | 
. . . . . . 7
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → 𝑀 ∈ 𝑉) | 
| 9 |   | f1osng 5545 | 
. . . . . . 7
⊢ ((1
∈ ℕ ∧ 𝑀
∈ 𝑉) → {〈1,
𝑀〉}:{1}–1-1-onto→{𝑀}) | 
| 10 | 6, 8, 9 | sylancr 414 | 
. . . . . 6
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → {〈1, 𝑀〉}:{1}–1-1-onto→{𝑀}) | 
| 11 |   | 1z 9352 | 
. . . . . . 7
⊢ 1 ∈
ℤ | 
| 12 |   | fzsn 10141 | 
. . . . . . 7
⊢ (1 ∈
ℤ → (1...1) = {1}) | 
| 13 |   | f1oeq2 5493 | 
. . . . . . 7
⊢ ((1...1)
= {1} → ({〈1, 𝑀〉}:(1...1)–1-1-onto→{𝑀} ↔ {〈1, 𝑀〉}:{1}–1-1-onto→{𝑀})) | 
| 14 | 11, 12, 13 | mp2b 8 | 
. . . . . 6
⊢
({〈1, 𝑀〉}:(1...1)–1-1-onto→{𝑀} ↔ {〈1, 𝑀〉}:{1}–1-1-onto→{𝑀}) | 
| 15 | 10, 14 | sylibr 134 | 
. . . . 5
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → {〈1, 𝑀〉}:(1...1)–1-1-onto→{𝑀}) | 
| 16 |   | elsni 3640 | 
. . . . . . . 8
⊢ (𝑚 ∈ {𝑀} → 𝑚 = 𝑀) | 
| 17 | 16 | adantl 277 | 
. . . . . . 7
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑚 ∈ {𝑀}) → 𝑚 = 𝑀) | 
| 18 | 17 | csbeq1d 3091 | 
. . . . . 6
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑚 ∈ {𝑀}) → ⦋𝑚 / 𝑘⦌𝐴 = ⦋𝑀 / 𝑘⦌𝐴) | 
| 19 |   | sumsnf.1 | 
. . . . . . . . . 10
⊢
Ⅎ𝑘𝐵 | 
| 20 | 19 | a1i 9 | 
. . . . . . . . 9
⊢ (𝑀 ∈ 𝑉 → Ⅎ𝑘𝐵) | 
| 21 |   | sumsnf.2 | 
. . . . . . . . 9
⊢ (𝑘 = 𝑀 → 𝐴 = 𝐵) | 
| 22 | 20, 21 | csbiegf 3128 | 
. . . . . . . 8
⊢ (𝑀 ∈ 𝑉 → ⦋𝑀 / 𝑘⦌𝐴 = 𝐵) | 
| 23 | 22 | ad2antrr 488 | 
. . . . . . 7
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑚 ∈ {𝑀}) → ⦋𝑀 / 𝑘⦌𝐴 = 𝐵) | 
| 24 |   | simplr 528 | 
. . . . . . 7
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑚 ∈ {𝑀}) → 𝐵 ∈ ℂ) | 
| 25 | 23, 24 | eqeltrd 2273 | 
. . . . . 6
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑚 ∈ {𝑀}) → ⦋𝑀 / 𝑘⦌𝐴 ∈ ℂ) | 
| 26 | 18, 25 | eqeltrd 2273 | 
. . . . 5
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑚 ∈ {𝑀}) → ⦋𝑚 / 𝑘⦌𝐴 ∈ ℂ) | 
| 27 | 22 | ad2antrr 488 | 
. . . . . 6
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑛 ∈ (1...1)) → ⦋𝑀 / 𝑘⦌𝐴 = 𝐵) | 
| 28 |   | elfz1eq 10110 | 
. . . . . . . . 9
⊢ (𝑛 ∈ (1...1) → 𝑛 = 1) | 
| 29 | 28 | fveq2d 5562 | 
. . . . . . . 8
⊢ (𝑛 ∈ (1...1) →
({〈1, 𝑀〉}‘𝑛) = ({〈1, 𝑀〉}‘1)) | 
| 30 |   | fvsng 5758 | 
. . . . . . . . 9
⊢ ((1
∈ ℕ ∧ 𝑀
∈ 𝑉) → ({〈1,
𝑀〉}‘1) = 𝑀) | 
| 31 | 6, 8, 30 | sylancr 414 | 
. . . . . . . 8
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → ({〈1, 𝑀〉}‘1) = 𝑀) | 
| 32 | 29, 31 | sylan9eqr 2251 | 
. . . . . . 7
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑛 ∈ (1...1)) → ({〈1, 𝑀〉}‘𝑛) = 𝑀) | 
| 33 | 32 | csbeq1d 3091 | 
. . . . . 6
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑛 ∈ (1...1)) →
⦋({〈1, 𝑀〉}‘𝑛) / 𝑘⦌𝐴 = ⦋𝑀 / 𝑘⦌𝐴) | 
| 34 | 28 | fveq2d 5562 | 
. . . . . . 7
⊢ (𝑛 ∈ (1...1) →
({〈1, 𝐵〉}‘𝑛) = ({〈1, 𝐵〉}‘1)) | 
| 35 |   | simpr 110 | 
. . . . . . . 8
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → 𝐵 ∈ ℂ) | 
| 36 |   | fvsng 5758 | 
. . . . . . . 8
⊢ ((1
∈ ℕ ∧ 𝐵
∈ ℂ) → ({〈1, 𝐵〉}‘1) = 𝐵) | 
| 37 | 6, 35, 36 | sylancr 414 | 
. . . . . . 7
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → ({〈1, 𝐵〉}‘1) = 𝐵) | 
| 38 | 34, 37 | sylan9eqr 2251 | 
. . . . . 6
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑛 ∈ (1...1)) → ({〈1, 𝐵〉}‘𝑛) = 𝐵) | 
| 39 | 27, 33, 38 | 3eqtr4rd 2240 | 
. . . . 5
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑛 ∈ (1...1)) → ({〈1, 𝐵〉}‘𝑛) = ⦋({〈1, 𝑀〉}‘𝑛) / 𝑘⦌𝐴) | 
| 40 | 5, 7, 15, 26, 39 | fsum3 11552 | 
. . . 4
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → Σ𝑚 ∈ {𝑀}⦋𝑚 / 𝑘⦌𝐴 = (seq1( + , (𝑛 ∈ ℕ ↦ if(𝑛 ≤ 1, ({〈1, 𝐵〉}‘𝑛), 0)))‘1)) | 
| 41 | 4, 40 | eqtrid 2241 | 
. . 3
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → Σ𝑘 ∈ {𝑀}𝐴 = (seq1( + , (𝑛 ∈ ℕ ↦ if(𝑛 ≤ 1, ({〈1, 𝐵〉}‘𝑛), 0)))‘1)) | 
| 42 |   | 1zzd 9353 | 
. . . 4
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → 1 ∈
ℤ) | 
| 43 |   | eqid 2196 | 
. . . . . 6
⊢ (𝑛 ∈ ℕ ↦ if(𝑛 ≤ 1, ({〈1, 𝐵〉}‘𝑛), 0)) = (𝑛 ∈ ℕ ↦ if(𝑛 ≤ 1, ({〈1, 𝐵〉}‘𝑛), 0)) | 
| 44 |   | breq1 4036 | 
. . . . . . 7
⊢ (𝑛 = 𝑢 → (𝑛 ≤ 1 ↔ 𝑢 ≤ 1)) | 
| 45 |   | fveq2 5558 | 
. . . . . . 7
⊢ (𝑛 = 𝑢 → ({〈1, 𝐵〉}‘𝑛) = ({〈1, 𝐵〉}‘𝑢)) | 
| 46 | 44, 45 | ifbieq1d 3583 | 
. . . . . 6
⊢ (𝑛 = 𝑢 → if(𝑛 ≤ 1, ({〈1, 𝐵〉}‘𝑛), 0) = if(𝑢 ≤ 1, ({〈1, 𝐵〉}‘𝑢), 0)) | 
| 47 |   | elnnuz 9638 | 
. . . . . . . 8
⊢ (𝑢 ∈ ℕ ↔ 𝑢 ∈
(ℤ≥‘1)) | 
| 48 | 47 | biimpri 133 | 
. . . . . . 7
⊢ (𝑢 ∈
(ℤ≥‘1) → 𝑢 ∈ ℕ) | 
| 49 | 48 | adantl 277 | 
. . . . . 6
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
→ 𝑢 ∈
ℕ) | 
| 50 |   | simpr 110 | 
. . . . . . . . . . 11
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ 𝑢 ≤ 1) →
𝑢 ≤ 1) | 
| 51 |   | eluzle 9613 | 
. . . . . . . . . . . 12
⊢ (𝑢 ∈
(ℤ≥‘1) → 1 ≤ 𝑢) | 
| 52 | 51 | ad2antlr 489 | 
. . . . . . . . . . 11
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ 𝑢 ≤ 1) → 1
≤ 𝑢) | 
| 53 |   | eluzelre 9611 | 
. . . . . . . . . . . . 13
⊢ (𝑢 ∈
(ℤ≥‘1) → 𝑢 ∈ ℝ) | 
| 54 | 53 | ad2antlr 489 | 
. . . . . . . . . . . 12
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ 𝑢 ≤ 1) →
𝑢 ∈
ℝ) | 
| 55 |   | 1red 8041 | 
. . . . . . . . . . . 12
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ 𝑢 ≤ 1) → 1
∈ ℝ) | 
| 56 | 54, 55 | letri3d 8142 | 
. . . . . . . . . . 11
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ 𝑢 ≤ 1) →
(𝑢 = 1 ↔ (𝑢 ≤ 1 ∧ 1 ≤ 𝑢))) | 
| 57 | 50, 52, 56 | mpbir2and 946 | 
. . . . . . . . . 10
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ 𝑢 ≤ 1) →
𝑢 = 1) | 
| 58 | 57 | fveq2d 5562 | 
. . . . . . . . 9
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ 𝑢 ≤ 1) →
({〈1, 𝐵〉}‘𝑢) = ({〈1, 𝐵〉}‘1)) | 
| 59 | 37 | ad2antrr 488 | 
. . . . . . . . 9
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ 𝑢 ≤ 1) →
({〈1, 𝐵〉}‘1) = 𝐵) | 
| 60 | 58, 59 | eqtrd 2229 | 
. . . . . . . 8
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ 𝑢 ≤ 1) →
({〈1, 𝐵〉}‘𝑢) = 𝐵) | 
| 61 | 35 | ad2antrr 488 | 
. . . . . . . 8
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ 𝑢 ≤ 1) →
𝐵 ∈
ℂ) | 
| 62 | 60, 61 | eqeltrd 2273 | 
. . . . . . 7
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ 𝑢 ≤ 1) →
({〈1, 𝐵〉}‘𝑢) ∈ ℂ) | 
| 63 |   | 0cnd 8019 | 
. . . . . . 7
⊢ ((((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
∧ ¬ 𝑢 ≤ 1)
→ 0 ∈ ℂ) | 
| 64 | 49 | nnzd 9447 | 
. . . . . . . 8
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
→ 𝑢 ∈
ℤ) | 
| 65 |   | 1zzd 9353 | 
. . . . . . . 8
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
→ 1 ∈ ℤ) | 
| 66 |   | zdcle 9402 | 
. . . . . . . 8
⊢ ((𝑢 ∈ ℤ ∧ 1 ∈
ℤ) → DECID 𝑢 ≤ 1) | 
| 67 | 64, 65, 66 | syl2anc 411 | 
. . . . . . 7
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
→ DECID 𝑢 ≤ 1) | 
| 68 | 62, 63, 67 | ifcldadc 3590 | 
. . . . . 6
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
→ if(𝑢 ≤ 1,
({〈1, 𝐵〉}‘𝑢), 0) ∈ ℂ) | 
| 69 | 43, 46, 49, 68 | fvmptd3 5655 | 
. . . . 5
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
→ ((𝑛 ∈ ℕ
↦ if(𝑛 ≤ 1,
({〈1, 𝐵〉}‘𝑛), 0))‘𝑢) = if(𝑢 ≤ 1, ({〈1, 𝐵〉}‘𝑢), 0)) | 
| 70 | 69, 68 | eqeltrd 2273 | 
. . . 4
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ 𝑢 ∈ (ℤ≥‘1))
→ ((𝑛 ∈ ℕ
↦ if(𝑛 ≤ 1,
({〈1, 𝐵〉}‘𝑛), 0))‘𝑢) ∈ ℂ) | 
| 71 |   | addcl 8004 | 
. . . . 5
⊢ ((𝑢 ∈ ℂ ∧ 𝑣 ∈ ℂ) → (𝑢 + 𝑣) ∈ ℂ) | 
| 72 | 71 | adantl 277 | 
. . . 4
⊢ (((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) ∧ (𝑢 ∈ ℂ ∧ 𝑣 ∈ ℂ)) → (𝑢 + 𝑣) ∈ ℂ) | 
| 73 | 42, 70, 72 | seq3-1 10554 | 
. . 3
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → (seq1( + , (𝑛 ∈ ℕ ↦ if(𝑛 ≤ 1, ({〈1, 𝐵〉}‘𝑛), 0)))‘1) = ((𝑛 ∈ ℕ ↦ if(𝑛 ≤ 1, ({〈1, 𝐵〉}‘𝑛), 0))‘1)) | 
| 74 | 41, 73 | eqtrd 2229 | 
. 2
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → Σ𝑘 ∈ {𝑀}𝐴 = ((𝑛 ∈ ℕ ↦ if(𝑛 ≤ 1, ({〈1, 𝐵〉}‘𝑛), 0))‘1)) | 
| 75 |   | 1le1 8599 | 
. . . . . 6
⊢ 1 ≤
1 | 
| 76 | 75 | iftruei 3567 | 
. . . . 5
⊢ if(1 ≤
1, ({〈1, 𝐵〉}‘1), 0) = ({〈1, 𝐵〉}‘1) | 
| 77 | 76, 37 | eqtrid 2241 | 
. . . 4
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → if(1 ≤ 1,
({〈1, 𝐵〉}‘1), 0) = 𝐵) | 
| 78 | 77, 35 | eqeltrd 2273 | 
. . 3
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → if(1 ≤ 1,
({〈1, 𝐵〉}‘1), 0) ∈
ℂ) | 
| 79 |   | breq1 4036 | 
. . . . 5
⊢ (𝑛 = 1 → (𝑛 ≤ 1 ↔ 1 ≤ 1)) | 
| 80 |   | fveq2 5558 | 
. . . . 5
⊢ (𝑛 = 1 → ({〈1, 𝐵〉}‘𝑛) = ({〈1, 𝐵〉}‘1)) | 
| 81 | 79, 80 | ifbieq1d 3583 | 
. . . 4
⊢ (𝑛 = 1 → if(𝑛 ≤ 1, ({〈1, 𝐵〉}‘𝑛), 0) = if(1 ≤ 1, ({〈1, 𝐵〉}‘1),
0)) | 
| 82 | 81, 43 | fvmptg 5637 | 
. . 3
⊢ ((1
∈ ℕ ∧ if(1 ≤ 1, ({〈1, 𝐵〉}‘1), 0) ∈ ℂ) →
((𝑛 ∈ ℕ ↦
if(𝑛 ≤ 1, ({〈1,
𝐵〉}‘𝑛), 0))‘1) = if(1 ≤ 1,
({〈1, 𝐵〉}‘1), 0)) | 
| 83 | 6, 78, 82 | sylancr 414 | 
. 2
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → ((𝑛 ∈ ℕ ↦ if(𝑛 ≤ 1, ({〈1, 𝐵〉}‘𝑛), 0))‘1) = if(1 ≤ 1, ({〈1,
𝐵〉}‘1),
0)) | 
| 84 | 74, 83, 77 | 3eqtrd 2233 | 
1
⊢ ((𝑀 ∈ 𝑉 ∧ 𝐵 ∈ ℂ) → Σ𝑘 ∈ {𝑀}𝐴 = 𝐵) |