| Step | Hyp | Ref
 | Expression | 
| 1 |   | iseqid3s.2 | 
. . 3
⊢ (𝜑 → 𝑁 ∈ (ℤ≥‘𝑀)) | 
| 2 |   | eluzfz2 10107 | 
. . 3
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → 𝑁 ∈ (𝑀...𝑁)) | 
| 3 |   | fveqeq2 5567 | 
. . . . 5
⊢ (𝑤 = 𝑀 → ((seq𝑀( + , 𝐹)‘𝑤) = 𝑍 ↔ (seq𝑀( + , 𝐹)‘𝑀) = 𝑍)) | 
| 4 | 3 | imbi2d 230 | 
. . . 4
⊢ (𝑤 = 𝑀 → ((𝜑 → (seq𝑀( + , 𝐹)‘𝑤) = 𝑍) ↔ (𝜑 → (seq𝑀( + , 𝐹)‘𝑀) = 𝑍))) | 
| 5 |   | fveqeq2 5567 | 
. . . . 5
⊢ (𝑤 = 𝑘 → ((seq𝑀( + , 𝐹)‘𝑤) = 𝑍 ↔ (seq𝑀( + , 𝐹)‘𝑘) = 𝑍)) | 
| 6 | 5 | imbi2d 230 | 
. . . 4
⊢ (𝑤 = 𝑘 → ((𝜑 → (seq𝑀( + , 𝐹)‘𝑤) = 𝑍) ↔ (𝜑 → (seq𝑀( + , 𝐹)‘𝑘) = 𝑍))) | 
| 7 |   | fveqeq2 5567 | 
. . . . 5
⊢ (𝑤 = (𝑘 + 1) → ((seq𝑀( + , 𝐹)‘𝑤) = 𝑍 ↔ (seq𝑀( + , 𝐹)‘(𝑘 + 1)) = 𝑍)) | 
| 8 | 7 | imbi2d 230 | 
. . . 4
⊢ (𝑤 = (𝑘 + 1) → ((𝜑 → (seq𝑀( + , 𝐹)‘𝑤) = 𝑍) ↔ (𝜑 → (seq𝑀( + , 𝐹)‘(𝑘 + 1)) = 𝑍))) | 
| 9 |   | fveqeq2 5567 | 
. . . . 5
⊢ (𝑤 = 𝑁 → ((seq𝑀( + , 𝐹)‘𝑤) = 𝑍 ↔ (seq𝑀( + , 𝐹)‘𝑁) = 𝑍)) | 
| 10 | 9 | imbi2d 230 | 
. . . 4
⊢ (𝑤 = 𝑁 → ((𝜑 → (seq𝑀( + , 𝐹)‘𝑤) = 𝑍) ↔ (𝜑 → (seq𝑀( + , 𝐹)‘𝑁) = 𝑍))) | 
| 11 |   | eluzel2 9606 | 
. . . . . . . 8
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → 𝑀 ∈ ℤ) | 
| 12 | 1, 11 | syl 14 | 
. . . . . . 7
⊢ (𝜑 → 𝑀 ∈ ℤ) | 
| 13 |   | iseqid3s.f | 
. . . . . . 7
⊢ ((𝜑 ∧ 𝑥 ∈ (ℤ≥‘𝑀)) → (𝐹‘𝑥) ∈ 𝑆) | 
| 14 |   | iseqid3s.cl | 
. . . . . . 7
⊢ ((𝜑 ∧ (𝑥 ∈ 𝑆 ∧ 𝑦 ∈ 𝑆)) → (𝑥 + 𝑦) ∈ 𝑆) | 
| 15 | 12, 13, 14 | seq3-1 10554 | 
. . . . . 6
⊢ (𝜑 → (seq𝑀( + , 𝐹)‘𝑀) = (𝐹‘𝑀)) | 
| 16 |   | iseqid3s.3 | 
. . . . . . . 8
⊢ ((𝜑 ∧ 𝑥 ∈ (𝑀...𝑁)) → (𝐹‘𝑥) = 𝑍) | 
| 17 | 16 | ralrimiva 2570 | 
. . . . . . 7
⊢ (𝜑 → ∀𝑥 ∈ (𝑀...𝑁)(𝐹‘𝑥) = 𝑍) | 
| 18 |   | eluzfz1 10106 | 
. . . . . . . 8
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → 𝑀 ∈ (𝑀...𝑁)) | 
| 19 |   | fveqeq2 5567 | 
. . . . . . . . 9
⊢ (𝑥 = 𝑀 → ((𝐹‘𝑥) = 𝑍 ↔ (𝐹‘𝑀) = 𝑍)) | 
| 20 | 19 | rspcv 2864 | 
. . . . . . . 8
⊢ (𝑀 ∈ (𝑀...𝑁) → (∀𝑥 ∈ (𝑀...𝑁)(𝐹‘𝑥) = 𝑍 → (𝐹‘𝑀) = 𝑍)) | 
| 21 | 1, 18, 20 | 3syl 17 | 
. . . . . . 7
⊢ (𝜑 → (∀𝑥 ∈ (𝑀...𝑁)(𝐹‘𝑥) = 𝑍 → (𝐹‘𝑀) = 𝑍)) | 
| 22 | 17, 21 | mpd 13 | 
. . . . . 6
⊢ (𝜑 → (𝐹‘𝑀) = 𝑍) | 
| 23 | 15, 22 | eqtrd 2229 | 
. . . . 5
⊢ (𝜑 → (seq𝑀( + , 𝐹)‘𝑀) = 𝑍) | 
| 24 | 23 | a1i 9 | 
. . . 4
⊢ (𝑁 ∈
(ℤ≥‘𝑀) → (𝜑 → (seq𝑀( + , 𝐹)‘𝑀) = 𝑍)) | 
| 25 |   | elfzouz 10226 | 
. . . . . . . . . . 11
⊢ (𝑘 ∈ (𝑀..^𝑁) → 𝑘 ∈ (ℤ≥‘𝑀)) | 
| 26 | 25 | adantl 277 | 
. . . . . . . . . 10
⊢ ((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) → 𝑘 ∈ (ℤ≥‘𝑀)) | 
| 27 | 13 | adantlr 477 | 
. . . . . . . . . 10
⊢ (((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) ∧ 𝑥 ∈ (ℤ≥‘𝑀)) → (𝐹‘𝑥) ∈ 𝑆) | 
| 28 | 14 | adantlr 477 | 
. . . . . . . . . 10
⊢ (((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) ∧ (𝑥 ∈ 𝑆 ∧ 𝑦 ∈ 𝑆)) → (𝑥 + 𝑦) ∈ 𝑆) | 
| 29 | 26, 27, 28 | seq3p1 10557 | 
. . . . . . . . 9
⊢ ((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) → (seq𝑀( + , 𝐹)‘(𝑘 + 1)) = ((seq𝑀( + , 𝐹)‘𝑘) + (𝐹‘(𝑘 + 1)))) | 
| 30 | 29 | adantr 276 | 
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) ∧ (seq𝑀( + , 𝐹)‘𝑘) = 𝑍) → (seq𝑀( + , 𝐹)‘(𝑘 + 1)) = ((seq𝑀( + , 𝐹)‘𝑘) + (𝐹‘(𝑘 + 1)))) | 
| 31 |   | simpr 110 | 
. . . . . . . . 9
⊢ (((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) ∧ (seq𝑀( + , 𝐹)‘𝑘) = 𝑍) → (seq𝑀( + , 𝐹)‘𝑘) = 𝑍) | 
| 32 |   | fveqeq2 5567 | 
. . . . . . . . . . 11
⊢ (𝑥 = (𝑘 + 1) → ((𝐹‘𝑥) = 𝑍 ↔ (𝐹‘(𝑘 + 1)) = 𝑍)) | 
| 33 | 17 | adantr 276 | 
. . . . . . . . . . 11
⊢ ((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) → ∀𝑥 ∈ (𝑀...𝑁)(𝐹‘𝑥) = 𝑍) | 
| 34 |   | fzofzp1 10303 | 
. . . . . . . . . . . 12
⊢ (𝑘 ∈ (𝑀..^𝑁) → (𝑘 + 1) ∈ (𝑀...𝑁)) | 
| 35 | 34 | adantl 277 | 
. . . . . . . . . . 11
⊢ ((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) → (𝑘 + 1) ∈ (𝑀...𝑁)) | 
| 36 | 32, 33, 35 | rspcdva 2873 | 
. . . . . . . . . 10
⊢ ((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) → (𝐹‘(𝑘 + 1)) = 𝑍) | 
| 37 | 36 | adantr 276 | 
. . . . . . . . 9
⊢ (((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) ∧ (seq𝑀( + , 𝐹)‘𝑘) = 𝑍) → (𝐹‘(𝑘 + 1)) = 𝑍) | 
| 38 | 31, 37 | oveq12d 5940 | 
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) ∧ (seq𝑀( + , 𝐹)‘𝑘) = 𝑍) → ((seq𝑀( + , 𝐹)‘𝑘) + (𝐹‘(𝑘 + 1))) = (𝑍 + 𝑍)) | 
| 39 |   | iseqid3s.1 | 
. . . . . . . . 9
⊢ (𝜑 → (𝑍 + 𝑍) = 𝑍) | 
| 40 | 39 | ad2antrr 488 | 
. . . . . . . 8
⊢ (((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) ∧ (seq𝑀( + , 𝐹)‘𝑘) = 𝑍) → (𝑍 + 𝑍) = 𝑍) | 
| 41 | 30, 38, 40 | 3eqtrd 2233 | 
. . . . . . 7
⊢ (((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) ∧ (seq𝑀( + , 𝐹)‘𝑘) = 𝑍) → (seq𝑀( + , 𝐹)‘(𝑘 + 1)) = 𝑍) | 
| 42 | 41 | ex 115 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑘 ∈ (𝑀..^𝑁)) → ((seq𝑀( + , 𝐹)‘𝑘) = 𝑍 → (seq𝑀( + , 𝐹)‘(𝑘 + 1)) = 𝑍)) | 
| 43 | 42 | expcom 116 | 
. . . . 5
⊢ (𝑘 ∈ (𝑀..^𝑁) → (𝜑 → ((seq𝑀( + , 𝐹)‘𝑘) = 𝑍 → (seq𝑀( + , 𝐹)‘(𝑘 + 1)) = 𝑍))) | 
| 44 | 43 | a2d 26 | 
. . . 4
⊢ (𝑘 ∈ (𝑀..^𝑁) → ((𝜑 → (seq𝑀( + , 𝐹)‘𝑘) = 𝑍) → (𝜑 → (seq𝑀( + , 𝐹)‘(𝑘 + 1)) = 𝑍))) | 
| 45 | 4, 6, 8, 10, 24, 44 | fzind2 10315 | 
. . 3
⊢ (𝑁 ∈ (𝑀...𝑁) → (𝜑 → (seq𝑀( + , 𝐹)‘𝑁) = 𝑍)) | 
| 46 | 1, 2, 45 | 3syl 17 | 
. 2
⊢ (𝜑 → (𝜑 → (seq𝑀( + , 𝐹)‘𝑁) = 𝑍)) | 
| 47 | 46 | pm2.43i 49 | 
1
⊢ (𝜑 → (seq𝑀( + , 𝐹)‘𝑁) = 𝑍) |