Metamath Proof Explorer


Theorem satffunlem1

Description: Lemma 1 for satffun : induction basis. (Contributed by AV, 28-Oct-2023)

Ref Expression
Assertion satffunlem1 ( ( 𝑀𝑉𝐸𝑊 ) → Fun ( ( 𝑀 Sat 𝐸 ) ‘ suc ∅ ) )

Proof

Step Hyp Ref Expression
1 satfv0fun ( ( 𝑀𝑉𝐸𝑊 ) → Fun ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) )
2 satffunlem1lem1 ( Fun ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) → Fun { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( ∃ 𝑣 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( 𝑥 = ( ( 1st𝑢 ) ⊼𝑔 ( 1st𝑣 ) ) ∧ 𝑦 = ( ( 𝑀m ω ) ∖ ( ( 2nd𝑢 ) ∩ ( 2nd𝑣 ) ) ) ) ∨ ∃ 𝑖 ∈ ω ( 𝑥 = ∀𝑔 𝑖 ( 1st𝑢 ) ∧ 𝑦 = { 𝑓 ∈ ( 𝑀m ω ) ∣ ∀ 𝑗𝑀 ( { ⟨ 𝑖 , 𝑗 ⟩ } ∪ ( 𝑓 ↾ ( ω ∖ { 𝑖 } ) ) ) ∈ ( 2nd𝑢 ) } ) ) } )
3 1 2 syl ( ( 𝑀𝑉𝐸𝑊 ) → Fun { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( ∃ 𝑣 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( 𝑥 = ( ( 1st𝑢 ) ⊼𝑔 ( 1st𝑣 ) ) ∧ 𝑦 = ( ( 𝑀m ω ) ∖ ( ( 2nd𝑢 ) ∩ ( 2nd𝑣 ) ) ) ) ∨ ∃ 𝑖 ∈ ω ( 𝑥 = ∀𝑔 𝑖 ( 1st𝑢 ) ∧ 𝑦 = { 𝑓 ∈ ( 𝑀m ω ) ∣ ∀ 𝑗𝑀 ( { ⟨ 𝑖 , 𝑗 ⟩ } ∪ ( 𝑓 ↾ ( ω ∖ { 𝑖 } ) ) ) ∈ ( 2nd𝑢 ) } ) ) } )
4 satffunlem1lem2 ( ( 𝑀𝑉𝐸𝑊 ) → ( dom ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ∩ dom { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( ∃ 𝑣 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( 𝑥 = ( ( 1st𝑢 ) ⊼𝑔 ( 1st𝑣 ) ) ∧ 𝑦 = ( ( 𝑀m ω ) ∖ ( ( 2nd𝑢 ) ∩ ( 2nd𝑣 ) ) ) ) ∨ ∃ 𝑖 ∈ ω ( 𝑥 = ∀𝑔 𝑖 ( 1st𝑢 ) ∧ 𝑦 = { 𝑓 ∈ ( 𝑀m ω ) ∣ ∀ 𝑗𝑀 ( { ⟨ 𝑖 , 𝑗 ⟩ } ∪ ( 𝑓 ↾ ( ω ∖ { 𝑖 } ) ) ) ∈ ( 2nd𝑢 ) } ) ) } ) = ∅ )
5 funun ( ( ( Fun ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ∧ Fun { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( ∃ 𝑣 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( 𝑥 = ( ( 1st𝑢 ) ⊼𝑔 ( 1st𝑣 ) ) ∧ 𝑦 = ( ( 𝑀m ω ) ∖ ( ( 2nd𝑢 ) ∩ ( 2nd𝑣 ) ) ) ) ∨ ∃ 𝑖 ∈ ω ( 𝑥 = ∀𝑔 𝑖 ( 1st𝑢 ) ∧ 𝑦 = { 𝑓 ∈ ( 𝑀m ω ) ∣ ∀ 𝑗𝑀 ( { ⟨ 𝑖 , 𝑗 ⟩ } ∪ ( 𝑓 ↾ ( ω ∖ { 𝑖 } ) ) ) ∈ ( 2nd𝑢 ) } ) ) } ) ∧ ( dom ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ∩ dom { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( ∃ 𝑣 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( 𝑥 = ( ( 1st𝑢 ) ⊼𝑔 ( 1st𝑣 ) ) ∧ 𝑦 = ( ( 𝑀m ω ) ∖ ( ( 2nd𝑢 ) ∩ ( 2nd𝑣 ) ) ) ) ∨ ∃ 𝑖 ∈ ω ( 𝑥 = ∀𝑔 𝑖 ( 1st𝑢 ) ∧ 𝑦 = { 𝑓 ∈ ( 𝑀m ω ) ∣ ∀ 𝑗𝑀 ( { ⟨ 𝑖 , 𝑗 ⟩ } ∪ ( 𝑓 ↾ ( ω ∖ { 𝑖 } ) ) ) ∈ ( 2nd𝑢 ) } ) ) } ) = ∅ ) → Fun ( ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ∪ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( ∃ 𝑣 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( 𝑥 = ( ( 1st𝑢 ) ⊼𝑔 ( 1st𝑣 ) ) ∧ 𝑦 = ( ( 𝑀m ω ) ∖ ( ( 2nd𝑢 ) ∩ ( 2nd𝑣 ) ) ) ) ∨ ∃ 𝑖 ∈ ω ( 𝑥 = ∀𝑔 𝑖 ( 1st𝑢 ) ∧ 𝑦 = { 𝑓 ∈ ( 𝑀m ω ) ∣ ∀ 𝑗𝑀 ( { ⟨ 𝑖 , 𝑗 ⟩ } ∪ ( 𝑓 ↾ ( ω ∖ { 𝑖 } ) ) ) ∈ ( 2nd𝑢 ) } ) ) } ) )
6 1 3 4 5 syl21anc ( ( 𝑀𝑉𝐸𝑊 ) → Fun ( ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ∪ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( ∃ 𝑣 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( 𝑥 = ( ( 1st𝑢 ) ⊼𝑔 ( 1st𝑣 ) ) ∧ 𝑦 = ( ( 𝑀m ω ) ∖ ( ( 2nd𝑢 ) ∩ ( 2nd𝑣 ) ) ) ) ∨ ∃ 𝑖 ∈ ω ( 𝑥 = ∀𝑔 𝑖 ( 1st𝑢 ) ∧ 𝑦 = { 𝑓 ∈ ( 𝑀m ω ) ∣ ∀ 𝑗𝑀 ( { ⟨ 𝑖 , 𝑗 ⟩ } ∪ ( 𝑓 ↾ ( ω ∖ { 𝑖 } ) ) ) ∈ ( 2nd𝑢 ) } ) ) } ) )
7 peano1 ∅ ∈ ω
8 eqid ( 𝑀 Sat 𝐸 ) = ( 𝑀 Sat 𝐸 )
9 8 satfvsuc ( ( 𝑀𝑉𝐸𝑊 ∧ ∅ ∈ ω ) → ( ( 𝑀 Sat 𝐸 ) ‘ suc ∅ ) = ( ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ∪ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( ∃ 𝑣 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( 𝑥 = ( ( 1st𝑢 ) ⊼𝑔 ( 1st𝑣 ) ) ∧ 𝑦 = ( ( 𝑀m ω ) ∖ ( ( 2nd𝑢 ) ∩ ( 2nd𝑣 ) ) ) ) ∨ ∃ 𝑖 ∈ ω ( 𝑥 = ∀𝑔 𝑖 ( 1st𝑢 ) ∧ 𝑦 = { 𝑓 ∈ ( 𝑀m ω ) ∣ ∀ 𝑗𝑀 ( { ⟨ 𝑖 , 𝑗 ⟩ } ∪ ( 𝑓 ↾ ( ω ∖ { 𝑖 } ) ) ) ∈ ( 2nd𝑢 ) } ) ) } ) )
10 7 9 mp3an3 ( ( 𝑀𝑉𝐸𝑊 ) → ( ( 𝑀 Sat 𝐸 ) ‘ suc ∅ ) = ( ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ∪ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( ∃ 𝑣 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( 𝑥 = ( ( 1st𝑢 ) ⊼𝑔 ( 1st𝑣 ) ) ∧ 𝑦 = ( ( 𝑀m ω ) ∖ ( ( 2nd𝑢 ) ∩ ( 2nd𝑣 ) ) ) ) ∨ ∃ 𝑖 ∈ ω ( 𝑥 = ∀𝑔 𝑖 ( 1st𝑢 ) ∧ 𝑦 = { 𝑓 ∈ ( 𝑀m ω ) ∣ ∀ 𝑗𝑀 ( { ⟨ 𝑖 , 𝑗 ⟩ } ∪ ( 𝑓 ↾ ( ω ∖ { 𝑖 } ) ) ) ∈ ( 2nd𝑢 ) } ) ) } ) )
11 10 funeqd ( ( 𝑀𝑉𝐸𝑊 ) → ( Fun ( ( 𝑀 Sat 𝐸 ) ‘ suc ∅ ) ↔ Fun ( ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ∪ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ∃ 𝑢 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( ∃ 𝑣 ∈ ( ( 𝑀 Sat 𝐸 ) ‘ ∅ ) ( 𝑥 = ( ( 1st𝑢 ) ⊼𝑔 ( 1st𝑣 ) ) ∧ 𝑦 = ( ( 𝑀m ω ) ∖ ( ( 2nd𝑢 ) ∩ ( 2nd𝑣 ) ) ) ) ∨ ∃ 𝑖 ∈ ω ( 𝑥 = ∀𝑔 𝑖 ( 1st𝑢 ) ∧ 𝑦 = { 𝑓 ∈ ( 𝑀m ω ) ∣ ∀ 𝑗𝑀 ( { ⟨ 𝑖 , 𝑗 ⟩ } ∪ ( 𝑓 ↾ ( ω ∖ { 𝑖 } ) ) ) ∈ ( 2nd𝑢 ) } ) ) } ) ) )
12 6 11 mpbird ( ( 𝑀𝑉𝐸𝑊 ) → Fun ( ( 𝑀 Sat 𝐸 ) ‘ suc ∅ ) )