Metamath Proof Explorer


Theorem lmbr3

Description: Express the binary relation "sequence F converges to point P " in a metric space using an arbitrary upper set of integers. (Contributed by Glauco Siliprandi, 5-Feb-2022)

Ref Expression
Hypotheses lmbr3.1 𝑘 𝐹
lmbr3.2 ( 𝜑𝐽 ∈ ( TopOn ‘ 𝑋 ) )
Assertion lmbr3 ( 𝜑 → ( 𝐹 ( ⇝𝑡𝐽 ) 𝑃 ↔ ( 𝐹 ∈ ( 𝑋pm ℂ ) ∧ 𝑃𝑋 ∧ ∀ 𝑢𝐽 ( 𝑃𝑢 → ∃ 𝑗 ∈ ℤ ∀ 𝑘 ∈ ( ℤ𝑗 ) ( 𝑘 ∈ dom 𝐹 ∧ ( 𝐹𝑘 ) ∈ 𝑢 ) ) ) ) )

Proof

Step Hyp Ref Expression
1 lmbr3.1 𝑘 𝐹
2 lmbr3.2 ( 𝜑𝐽 ∈ ( TopOn ‘ 𝑋 ) )
3 2 lmbr3v ( 𝜑 → ( 𝐹 ( ⇝𝑡𝐽 ) 𝑃 ↔ ( 𝐹 ∈ ( 𝑋pm ℂ ) ∧ 𝑃𝑋 ∧ ∀ 𝑣𝐽 ( 𝑃𝑣 → ∃ 𝑖 ∈ ℤ ∀ 𝑙 ∈ ( ℤ𝑖 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑣 ) ) ) ) )
4 eleq2w ( 𝑣 = 𝑢 → ( 𝑃𝑣𝑃𝑢 ) )
5 eleq2w ( 𝑣 = 𝑢 → ( ( 𝐹𝑙 ) ∈ 𝑣 ↔ ( 𝐹𝑙 ) ∈ 𝑢 ) )
6 5 anbi2d ( 𝑣 = 𝑢 → ( ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑣 ) ↔ ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑢 ) ) )
7 6 rexralbidv ( 𝑣 = 𝑢 → ( ∃ 𝑖 ∈ ℤ ∀ 𝑙 ∈ ( ℤ𝑖 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑣 ) ↔ ∃ 𝑖 ∈ ℤ ∀ 𝑙 ∈ ( ℤ𝑖 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑢 ) ) )
8 fveq2 ( 𝑖 = 𝑗 → ( ℤ𝑖 ) = ( ℤ𝑗 ) )
9 8 raleqdv ( 𝑖 = 𝑗 → ( ∀ 𝑙 ∈ ( ℤ𝑖 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑢 ) ↔ ∀ 𝑙 ∈ ( ℤ𝑗 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑢 ) ) )
10 nfcv 𝑘 𝑙
11 1 nfdm 𝑘 dom 𝐹
12 10 11 nfel 𝑘 𝑙 ∈ dom 𝐹
13 1 10 nffv 𝑘 ( 𝐹𝑙 )
14 nfcv 𝑘 𝑢
15 13 14 nfel 𝑘 ( 𝐹𝑙 ) ∈ 𝑢
16 12 15 nfan 𝑘 ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑢 )
17 nfv 𝑙 ( 𝑘 ∈ dom 𝐹 ∧ ( 𝐹𝑘 ) ∈ 𝑢 )
18 eleq1w ( 𝑙 = 𝑘 → ( 𝑙 ∈ dom 𝐹𝑘 ∈ dom 𝐹 ) )
19 fveq2 ( 𝑙 = 𝑘 → ( 𝐹𝑙 ) = ( 𝐹𝑘 ) )
20 19 eleq1d ( 𝑙 = 𝑘 → ( ( 𝐹𝑙 ) ∈ 𝑢 ↔ ( 𝐹𝑘 ) ∈ 𝑢 ) )
21 18 20 anbi12d ( 𝑙 = 𝑘 → ( ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑢 ) ↔ ( 𝑘 ∈ dom 𝐹 ∧ ( 𝐹𝑘 ) ∈ 𝑢 ) ) )
22 16 17 21 cbvralw ( ∀ 𝑙 ∈ ( ℤ𝑗 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑢 ) ↔ ∀ 𝑘 ∈ ( ℤ𝑗 ) ( 𝑘 ∈ dom 𝐹 ∧ ( 𝐹𝑘 ) ∈ 𝑢 ) )
23 9 22 bitrdi ( 𝑖 = 𝑗 → ( ∀ 𝑙 ∈ ( ℤ𝑖 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑢 ) ↔ ∀ 𝑘 ∈ ( ℤ𝑗 ) ( 𝑘 ∈ dom 𝐹 ∧ ( 𝐹𝑘 ) ∈ 𝑢 ) ) )
24 23 cbvrexvw ( ∃ 𝑖 ∈ ℤ ∀ 𝑙 ∈ ( ℤ𝑖 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑢 ) ↔ ∃ 𝑗 ∈ ℤ ∀ 𝑘 ∈ ( ℤ𝑗 ) ( 𝑘 ∈ dom 𝐹 ∧ ( 𝐹𝑘 ) ∈ 𝑢 ) )
25 7 24 bitrdi ( 𝑣 = 𝑢 → ( ∃ 𝑖 ∈ ℤ ∀ 𝑙 ∈ ( ℤ𝑖 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑣 ) ↔ ∃ 𝑗 ∈ ℤ ∀ 𝑘 ∈ ( ℤ𝑗 ) ( 𝑘 ∈ dom 𝐹 ∧ ( 𝐹𝑘 ) ∈ 𝑢 ) ) )
26 4 25 imbi12d ( 𝑣 = 𝑢 → ( ( 𝑃𝑣 → ∃ 𝑖 ∈ ℤ ∀ 𝑙 ∈ ( ℤ𝑖 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑣 ) ) ↔ ( 𝑃𝑢 → ∃ 𝑗 ∈ ℤ ∀ 𝑘 ∈ ( ℤ𝑗 ) ( 𝑘 ∈ dom 𝐹 ∧ ( 𝐹𝑘 ) ∈ 𝑢 ) ) ) )
27 26 cbvralvw ( ∀ 𝑣𝐽 ( 𝑃𝑣 → ∃ 𝑖 ∈ ℤ ∀ 𝑙 ∈ ( ℤ𝑖 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑣 ) ) ↔ ∀ 𝑢𝐽 ( 𝑃𝑢 → ∃ 𝑗 ∈ ℤ ∀ 𝑘 ∈ ( ℤ𝑗 ) ( 𝑘 ∈ dom 𝐹 ∧ ( 𝐹𝑘 ) ∈ 𝑢 ) ) )
28 27 3anbi3i ( ( 𝐹 ∈ ( 𝑋pm ℂ ) ∧ 𝑃𝑋 ∧ ∀ 𝑣𝐽 ( 𝑃𝑣 → ∃ 𝑖 ∈ ℤ ∀ 𝑙 ∈ ( ℤ𝑖 ) ( 𝑙 ∈ dom 𝐹 ∧ ( 𝐹𝑙 ) ∈ 𝑣 ) ) ) ↔ ( 𝐹 ∈ ( 𝑋pm ℂ ) ∧ 𝑃𝑋 ∧ ∀ 𝑢𝐽 ( 𝑃𝑢 → ∃ 𝑗 ∈ ℤ ∀ 𝑘 ∈ ( ℤ𝑗 ) ( 𝑘 ∈ dom 𝐹 ∧ ( 𝐹𝑘 ) ∈ 𝑢 ) ) ) )
29 3 28 bitrdi ( 𝜑 → ( 𝐹 ( ⇝𝑡𝐽 ) 𝑃 ↔ ( 𝐹 ∈ ( 𝑋pm ℂ ) ∧ 𝑃𝑋 ∧ ∀ 𝑢𝐽 ( 𝑃𝑢 → ∃ 𝑗 ∈ ℤ ∀ 𝑘 ∈ ( ℤ𝑗 ) ( 𝑘 ∈ dom 𝐹 ∧ ( 𝐹𝑘 ) ∈ 𝑢 ) ) ) ) )