This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: Define the superior limit of an infinite sequence of extended real numbers. Definition 12-4.1 of Gleason p. 175. See limsupval for its value. (Contributed by NM, 26-Oct-2005) (Revised by AV, 11-Sep-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-limsup | ⊢ lim sup = ( 𝑥 ∈ V ↦ inf ( ran ( 𝑘 ∈ ℝ ↦ sup ( ( ( 𝑥 “ ( 𝑘 [,) +∞ ) ) ∩ ℝ* ) , ℝ* , < ) ) , ℝ* , < ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | clsp | ⊢ lim sup | |
| 1 | vx | ⊢ 𝑥 | |
| 2 | cvv | ⊢ V | |
| 3 | vk | ⊢ 𝑘 | |
| 4 | cr | ⊢ ℝ | |
| 5 | 1 | cv | ⊢ 𝑥 |
| 6 | 3 | cv | ⊢ 𝑘 |
| 7 | cico | ⊢ [,) | |
| 8 | cpnf | ⊢ +∞ | |
| 9 | 6 8 7 | co | ⊢ ( 𝑘 [,) +∞ ) |
| 10 | 5 9 | cima | ⊢ ( 𝑥 “ ( 𝑘 [,) +∞ ) ) |
| 11 | cxr | ⊢ ℝ* | |
| 12 | 10 11 | cin | ⊢ ( ( 𝑥 “ ( 𝑘 [,) +∞ ) ) ∩ ℝ* ) |
| 13 | clt | ⊢ < | |
| 14 | 12 11 13 | csup | ⊢ sup ( ( ( 𝑥 “ ( 𝑘 [,) +∞ ) ) ∩ ℝ* ) , ℝ* , < ) |
| 15 | 3 4 14 | cmpt | ⊢ ( 𝑘 ∈ ℝ ↦ sup ( ( ( 𝑥 “ ( 𝑘 [,) +∞ ) ) ∩ ℝ* ) , ℝ* , < ) ) |
| 16 | 15 | crn | ⊢ ran ( 𝑘 ∈ ℝ ↦ sup ( ( ( 𝑥 “ ( 𝑘 [,) +∞ ) ) ∩ ℝ* ) , ℝ* , < ) ) |
| 17 | 16 11 13 | cinf | ⊢ inf ( ran ( 𝑘 ∈ ℝ ↦ sup ( ( ( 𝑥 “ ( 𝑘 [,) +∞ ) ) ∩ ℝ* ) , ℝ* , < ) ) , ℝ* , < ) |
| 18 | 1 2 17 | cmpt | ⊢ ( 𝑥 ∈ V ↦ inf ( ran ( 𝑘 ∈ ℝ ↦ sup ( ( ( 𝑥 “ ( 𝑘 [,) +∞ ) ) ∩ ℝ* ) , ℝ* , < ) ) , ℝ* , < ) ) |
| 19 | 0 18 | wceq | ⊢ lim sup = ( 𝑥 ∈ V ↦ inf ( ran ( 𝑘 ∈ ℝ ↦ sup ( ( ( 𝑥 “ ( 𝑘 [,) +∞ ) ) ∩ ℝ* ) , ℝ* , < ) ) , ℝ* , < ) ) |