| Step | Hyp | Ref
 | Expression | 
| 1 |   | fsumcvg3.4 | 
. . . . 5
⊢ (𝜑 → 𝐴 ⊆ 𝑍) | 
| 2 |   | fsumcvg3.1 | 
. . . . . 6
⊢ 𝑍 =
(ℤ≥‘𝑀) | 
| 3 |   | uzssz 9621 | 
. . . . . . 7
⊢
(ℤ≥‘𝑀) ⊆ ℤ | 
| 4 |   | zssre 9333 | 
. . . . . . 7
⊢ ℤ
⊆ ℝ | 
| 5 | 3, 4 | sstri 3192 | 
. . . . . 6
⊢
(ℤ≥‘𝑀) ⊆ ℝ | 
| 6 | 2, 5 | eqsstri 3215 | 
. . . . 5
⊢ 𝑍 ⊆
ℝ | 
| 7 | 1, 6 | sstrdi 3195 | 
. . . 4
⊢ (𝜑 → 𝐴 ⊆ ℝ) | 
| 8 |   | fsumcvg3.3 | 
. . . 4
⊢ (𝜑 → 𝐴 ∈ Fin) | 
| 9 |   | fimaxre2 11392 | 
. . . 4
⊢ ((𝐴 ⊆ ℝ ∧ 𝐴 ∈ Fin) → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥) | 
| 10 | 7, 8, 9 | syl2anc 411 | 
. . 3
⊢ (𝜑 → ∃𝑥 ∈ ℝ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥) | 
| 11 |   | arch 9246 | 
. . . . 5
⊢ (𝑥 ∈ ℝ →
∃𝑚 ∈ ℕ
𝑥 < 𝑚) | 
| 12 | 11 | ad2antrl 490 | 
. . . 4
⊢ ((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) → ∃𝑚 ∈ ℕ 𝑥 < 𝑚) | 
| 13 |   | fsumcvg3.2 | 
. . . . . . 7
⊢ (𝜑 → 𝑀 ∈ ℤ) | 
| 14 | 13 | ad2antrr 488 | 
. . . . . 6
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → 𝑀 ∈ ℤ) | 
| 15 |   | simprl 529 | 
. . . . . . . 8
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → 𝑚 ∈ ℕ) | 
| 16 | 15 | nnzd 9447 | 
. . . . . . 7
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → 𝑚 ∈ ℤ) | 
| 17 |   | zmaxcl 11389 | 
. . . . . . 7
⊢ ((𝑚 ∈ ℤ ∧ 𝑀 ∈ ℤ) →
sup({𝑚, 𝑀}, ℝ, < ) ∈
ℤ) | 
| 18 | 16, 14, 17 | syl2anc 411 | 
. . . . . 6
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → sup({𝑚, 𝑀}, ℝ, < ) ∈
ℤ) | 
| 19 | 15 | nnred 9003 | 
. . . . . . 7
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → 𝑚 ∈ ℝ) | 
| 20 | 14 | zred 9448 | 
. . . . . . 7
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → 𝑀 ∈ ℝ) | 
| 21 |   | maxle2 11377 | 
. . . . . . 7
⊢ ((𝑚 ∈ ℝ ∧ 𝑀 ∈ ℝ) → 𝑀 ≤ sup({𝑚, 𝑀}, ℝ, < )) | 
| 22 | 19, 20, 21 | syl2anc 411 | 
. . . . . 6
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → 𝑀 ≤ sup({𝑚, 𝑀}, ℝ, < )) | 
| 23 |   | eluz2 9607 | 
. . . . . 6
⊢
(sup({𝑚, 𝑀}, ℝ, < ) ∈
(ℤ≥‘𝑀) ↔ (𝑀 ∈ ℤ ∧ sup({𝑚, 𝑀}, ℝ, < ) ∈ ℤ ∧
𝑀 ≤ sup({𝑚, 𝑀}, ℝ, < ))) | 
| 24 | 14, 18, 22, 23 | syl3anbrc 1183 | 
. . . . 5
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → sup({𝑚, 𝑀}, ℝ, < ) ∈
(ℤ≥‘𝑀)) | 
| 25 | 14 | adantr 276 | 
. . . . . . . . 9
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑀 ∈ ℤ) | 
| 26 | 18 | adantr 276 | 
. . . . . . . . 9
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → sup({𝑚, 𝑀}, ℝ, < ) ∈
ℤ) | 
| 27 | 1, 2 | sseqtrdi 3231 | 
. . . . . . . . . . . 12
⊢ (𝜑 → 𝐴 ⊆ (ℤ≥‘𝑀)) | 
| 28 | 27 | ad3antrrr 492 | 
. . . . . . . . . . 11
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝐴 ⊆ (ℤ≥‘𝑀)) | 
| 29 | 28, 3 | sstrdi 3195 | 
. . . . . . . . . 10
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝐴 ⊆ ℤ) | 
| 30 |   | simpr 110 | 
. . . . . . . . . 10
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑧 ∈ 𝐴) | 
| 31 | 29, 30 | sseldd 3184 | 
. . . . . . . . 9
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑧 ∈ ℤ) | 
| 32 | 25, 26, 31 | 3jca 1179 | 
. . . . . . . 8
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → (𝑀 ∈ ℤ ∧ sup({𝑚, 𝑀}, ℝ, < ) ∈ ℤ ∧
𝑧 ∈
ℤ)) | 
| 33 | 27 | ad2antrr 488 | 
. . . . . . . . . . 11
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → 𝐴 ⊆ (ℤ≥‘𝑀)) | 
| 34 | 33 | sselda 3183 | 
. . . . . . . . . 10
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑧 ∈ (ℤ≥‘𝑀)) | 
| 35 |   | eluzle 9613 | 
. . . . . . . . . 10
⊢ (𝑧 ∈
(ℤ≥‘𝑀) → 𝑀 ≤ 𝑧) | 
| 36 | 34, 35 | syl 14 | 
. . . . . . . . 9
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑀 ≤ 𝑧) | 
| 37 | 31 | zred 9448 | 
. . . . . . . . . 10
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑧 ∈ ℝ) | 
| 38 | 19 | adantr 276 | 
. . . . . . . . . 10
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑚 ∈ ℝ) | 
| 39 | 26 | zred 9448 | 
. . . . . . . . . 10
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → sup({𝑚, 𝑀}, ℝ, < ) ∈
ℝ) | 
| 40 |   | simprl 529 | 
. . . . . . . . . . . 12
⊢ ((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) → 𝑥 ∈ ℝ) | 
| 41 | 40 | ad2antrr 488 | 
. . . . . . . . . . 11
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑥 ∈ ℝ) | 
| 42 |   | breq1 4036 | 
. . . . . . . . . . . 12
⊢ (𝑦 = 𝑧 → (𝑦 ≤ 𝑥 ↔ 𝑧 ≤ 𝑥)) | 
| 43 |   | simprr 531 | 
. . . . . . . . . . . . 13
⊢ ((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) → ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥) | 
| 44 | 43 | ad2antrr 488 | 
. . . . . . . . . . . 12
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥) | 
| 45 | 42, 44, 30 | rspcdva 2873 | 
. . . . . . . . . . 11
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑧 ≤ 𝑥) | 
| 46 |   | simplrr 536 | 
. . . . . . . . . . . 12
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑥 < 𝑚) | 
| 47 | 41, 38, 46 | ltled 8145 | 
. . . . . . . . . . 11
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑥 ≤ 𝑚) | 
| 48 | 37, 41, 38, 45, 47 | letrd 8150 | 
. . . . . . . . . 10
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑧 ≤ 𝑚) | 
| 49 | 20 | adantr 276 | 
. . . . . . . . . . 11
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑀 ∈ ℝ) | 
| 50 |   | maxle1 11376 | 
. . . . . . . . . . 11
⊢ ((𝑚 ∈ ℝ ∧ 𝑀 ∈ ℝ) → 𝑚 ≤ sup({𝑚, 𝑀}, ℝ, < )) | 
| 51 | 38, 49, 50 | syl2anc 411 | 
. . . . . . . . . 10
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑚 ≤ sup({𝑚, 𝑀}, ℝ, < )) | 
| 52 | 37, 38, 39, 48, 51 | letrd 8150 | 
. . . . . . . . 9
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑧 ≤ sup({𝑚, 𝑀}, ℝ, < )) | 
| 53 | 36, 52 | jca 306 | 
. . . . . . . 8
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → (𝑀 ≤ 𝑧 ∧ 𝑧 ≤ sup({𝑚, 𝑀}, ℝ, < ))) | 
| 54 |   | elfz2 10090 | 
. . . . . . . 8
⊢ (𝑧 ∈ (𝑀...sup({𝑚, 𝑀}, ℝ, < )) ↔ ((𝑀 ∈ ℤ ∧ sup({𝑚, 𝑀}, ℝ, < ) ∈ ℤ ∧
𝑧 ∈ ℤ) ∧
(𝑀 ≤ 𝑧 ∧ 𝑧 ≤ sup({𝑚, 𝑀}, ℝ, < )))) | 
| 55 | 32, 53, 54 | sylanbrc 417 | 
. . . . . . 7
⊢ ((((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) ∧ 𝑧 ∈ 𝐴) → 𝑧 ∈ (𝑀...sup({𝑚, 𝑀}, ℝ, < ))) | 
| 56 | 55 | ex 115 | 
. . . . . 6
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → (𝑧 ∈ 𝐴 → 𝑧 ∈ (𝑀...sup({𝑚, 𝑀}, ℝ, < )))) | 
| 57 | 56 | ssrdv 3189 | 
. . . . 5
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → 𝐴 ⊆ (𝑀...sup({𝑚, 𝑀}, ℝ, < ))) | 
| 58 |   | oveq2 5930 | 
. . . . . . 7
⊢ (𝑛 = sup({𝑚, 𝑀}, ℝ, < ) → (𝑀...𝑛) = (𝑀...sup({𝑚, 𝑀}, ℝ, < ))) | 
| 59 | 58 | sseq2d 3213 | 
. . . . . 6
⊢ (𝑛 = sup({𝑚, 𝑀}, ℝ, < ) → (𝐴 ⊆ (𝑀...𝑛) ↔ 𝐴 ⊆ (𝑀...sup({𝑚, 𝑀}, ℝ, < )))) | 
| 60 | 59 | rspcev 2868 | 
. . . . 5
⊢
((sup({𝑚, 𝑀}, ℝ, < ) ∈
(ℤ≥‘𝑀) ∧ 𝐴 ⊆ (𝑀...sup({𝑚, 𝑀}, ℝ, < ))) → ∃𝑛 ∈
(ℤ≥‘𝑀)𝐴 ⊆ (𝑀...𝑛)) | 
| 61 | 24, 57, 60 | syl2anc 411 | 
. . . 4
⊢ (((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) ∧ (𝑚 ∈ ℕ ∧ 𝑥 < 𝑚)) → ∃𝑛 ∈ (ℤ≥‘𝑀)𝐴 ⊆ (𝑀...𝑛)) | 
| 62 | 12, 61 | rexlimddv 2619 | 
. . 3
⊢ ((𝜑 ∧ (𝑥 ∈ ℝ ∧ ∀𝑦 ∈ 𝐴 𝑦 ≤ 𝑥)) → ∃𝑛 ∈ (ℤ≥‘𝑀)𝐴 ⊆ (𝑀...𝑛)) | 
| 63 | 10, 62 | rexlimddv 2619 | 
. 2
⊢ (𝜑 → ∃𝑛 ∈ (ℤ≥‘𝑀)𝐴 ⊆ (𝑀...𝑛)) | 
| 64 | 2 | eleq2i 2263 | 
. . . . . 6
⊢ (𝑘 ∈ 𝑍 ↔ 𝑘 ∈ (ℤ≥‘𝑀)) | 
| 65 |   | fsumcvg3.5 | 
. . . . . 6
⊢ ((𝜑 ∧ 𝑘 ∈ 𝑍) → (𝐹‘𝑘) = if(𝑘 ∈ 𝐴, 𝐵, 0)) | 
| 66 | 64, 65 | sylan2br 288 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑘 ∈ (ℤ≥‘𝑀)) → (𝐹‘𝑘) = if(𝑘 ∈ 𝐴, 𝐵, 0)) | 
| 67 | 66 | adantlr 477 | 
. . . 4
⊢ (((𝜑 ∧ (𝑛 ∈ (ℤ≥‘𝑀) ∧ 𝐴 ⊆ (𝑀...𝑛))) ∧ 𝑘 ∈ (ℤ≥‘𝑀)) → (𝐹‘𝑘) = if(𝑘 ∈ 𝐴, 𝐵, 0)) | 
| 68 |   | simprl 529 | 
. . . 4
⊢ ((𝜑 ∧ (𝑛 ∈ (ℤ≥‘𝑀) ∧ 𝐴 ⊆ (𝑀...𝑛))) → 𝑛 ∈ (ℤ≥‘𝑀)) | 
| 69 |   | fsumcvg3.6 | 
. . . . 5
⊢ ((𝜑 ∧ 𝑘 ∈ 𝐴) → 𝐵 ∈ ℂ) | 
| 70 | 69 | adantlr 477 | 
. . . 4
⊢ (((𝜑 ∧ (𝑛 ∈ (ℤ≥‘𝑀) ∧ 𝐴 ⊆ (𝑀...𝑛))) ∧ 𝑘 ∈ 𝐴) → 𝐵 ∈ ℂ) | 
| 71 |   | fisumcvg3.dc | 
. . . . 5
⊢ ((𝜑 ∧ 𝑘 ∈ (ℤ≥‘𝑀)) → DECID
𝑘 ∈ 𝐴) | 
| 72 | 71 | adantlr 477 | 
. . . 4
⊢ (((𝜑 ∧ (𝑛 ∈ (ℤ≥‘𝑀) ∧ 𝐴 ⊆ (𝑀...𝑛))) ∧ 𝑘 ∈ (ℤ≥‘𝑀)) → DECID
𝑘 ∈ 𝐴) | 
| 73 |   | simprr 531 | 
. . . 4
⊢ ((𝜑 ∧ (𝑛 ∈ (ℤ≥‘𝑀) ∧ 𝐴 ⊆ (𝑀...𝑛))) → 𝐴 ⊆ (𝑀...𝑛)) | 
| 74 | 67, 68, 70, 72, 73 | fsum3cvg2 11559 | 
. . 3
⊢ ((𝜑 ∧ (𝑛 ∈ (ℤ≥‘𝑀) ∧ 𝐴 ⊆ (𝑀...𝑛))) → seq𝑀( + , 𝐹) ⇝ (seq𝑀( + , 𝐹)‘𝑛)) | 
| 75 |   | climrel 11445 | 
. . . 4
⊢ Rel
⇝ | 
| 76 | 75 | releldmi 4905 | 
. . 3
⊢ (seq𝑀( + , 𝐹) ⇝ (seq𝑀( + , 𝐹)‘𝑛) → seq𝑀( + , 𝐹) ∈ dom ⇝ ) | 
| 77 | 74, 76 | syl 14 | 
. 2
⊢ ((𝜑 ∧ (𝑛 ∈ (ℤ≥‘𝑀) ∧ 𝐴 ⊆ (𝑀...𝑛))) → seq𝑀( + , 𝐹) ∈ dom ⇝ ) | 
| 78 | 63, 77 | rexlimddv 2619 | 
1
⊢ (𝜑 → seq𝑀( + , 𝐹) ∈ dom ⇝ ) |