Metamath Proof Explorer


Theorem tmachlem-exagreecover

Description: Particular properties of the finite cover of agreesets. (Contributed by Ender Ting, 28-Jul-2026)

Ref Expression
Hypotheses tmach.finalph ( 𝜑𝑈 ∈ Fin )
tmach.exindex ( 𝜑𝐼 ∈ V )
tmach.tapelist ( 𝜑𝑇 = ( 𝑈m 𝐼 ) )
tmach.scanmap ( 𝜑𝑆 : 𝑇 ⟶ ( 𝒫 𝐼 ∩ Fin ) )
tmach.agreemap ( 𝜑𝐴 = ( 𝑧𝑇 ↦ { 𝑦𝑇 ∣ ( 𝑦 ↾ ( 𝑆𝑧 ) ) = ( 𝑧 ↾ ( 𝑆𝑧 ) ) } ) )
tmach.agreement ( 𝜑 → ∀ 𝑧𝑇𝑦 ∈ ( 𝐴𝑧 ) ( 𝑆𝑦 ) = ( 𝑆𝑧 ) )
Assertion tmachlem-exagreecover ( 𝜑 → ∃ 𝑎 ( 𝑎 ⊆ ran 𝐴𝑎 ∈ Fin ∧ 𝑇 = 𝑎 ) )

Proof

Step Hyp Ref Expression
1 tmach.finalph ( 𝜑𝑈 ∈ Fin )
2 tmach.exindex ( 𝜑𝐼 ∈ V )
3 tmach.tapelist ( 𝜑𝑇 = ( 𝑈m 𝐼 ) )
4 tmach.scanmap ( 𝜑𝑆 : 𝑇 ⟶ ( 𝒫 𝐼 ∩ Fin ) )
5 tmach.agreemap ( 𝜑𝐴 = ( 𝑧𝑇 ↦ { 𝑦𝑇 ∣ ( 𝑦 ↾ ( 𝑆𝑧 ) ) = ( 𝑧 ↾ ( 𝑆𝑧 ) ) } ) )
6 tmach.agreement ( 𝜑 → ∀ 𝑧𝑇𝑦 ∈ ( 𝐴𝑧 ) ( 𝑆𝑦 ) = ( 𝑆𝑧 ) )
7 1 2 3 4 5 6 tmachlem-extpcover ( 𝜑 → ∃ 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 )
8 df-rex ( ∃ 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ↔ ∃ 𝑎 ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) )
9 7 8 sylib ( 𝜑 → ∃ 𝑎 ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) )
10 simprl ( ( 𝜑 ∧ ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) ) → 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) )
11 10 elin1d ( ( 𝜑 ∧ ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) ) → 𝑎 ∈ 𝒫 ran 𝐴 )
12 11 elpwid ( ( 𝜑 ∧ ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) ) → 𝑎 ⊆ ran 𝐴 )
13 10 elin2d ( ( 𝜑 ∧ ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) ) → 𝑎 ∈ Fin )
14 1 2 3 4 5 6 tmachlem-tpbase ( 𝜑 ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑇 )
15 14 adantr ( ( 𝜑 ∧ ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) ) → ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑇 )
16 simprr ( ( 𝜑 ∧ ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) ) → ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 )
17 15 16 eqtr3d ( ( 𝜑 ∧ ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) ) → 𝑇 = 𝑎 )
18 12 13 17 3jca ( ( 𝜑 ∧ ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) ) → ( 𝑎 ⊆ ran 𝐴𝑎 ∈ Fin ∧ 𝑇 = 𝑎 ) )
19 18 ex ( 𝜑 → ( ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) → ( 𝑎 ⊆ ran 𝐴𝑎 ∈ Fin ∧ 𝑇 = 𝑎 ) ) )
20 19 eximdv ( 𝜑 → ( ∃ 𝑎 ( 𝑎 ∈ ( 𝒫 ran 𝐴 ∩ Fin ) ∧ ( ∏t ‘ ( 𝑖𝐼 ↦ 𝒫 𝑈 ) ) = 𝑎 ) → ∃ 𝑎 ( 𝑎 ⊆ ran 𝐴𝑎 ∈ Fin ∧ 𝑇 = 𝑎 ) ) )
21 9 20 mpd ( 𝜑 → ∃ 𝑎 ( 𝑎 ⊆ ran 𝐴𝑎 ∈ Fin ∧ 𝑇 = 𝑎 ) )