Metamath Proof Explorer

Theorem satf0sucom

Description: The satisfaction predicate as function over wff codes in the empty model with an empty binary relation at a successor of _om . (Contributed by AV, 14-Sep-2023)

		Ref	Expression
	Assertion	satf0sucom	⊢ ( 𝑁 ∈ suc ω → ( ( ∅ Sat ∅ ) ‘ 𝑁 ) = ( rec ( ( 𝑓 ∈ V ↦ ( 𝑓 ∪ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑢 ∈ 𝑓 ( ∃ 𝑣 ∈ 𝑓 𝑥 = ( ( 1^st ‘ 𝑢 ) ⊼_𝑔 ( 1^st ‘ 𝑣 ) ) ∨ ∃ 𝑖 ∈ ω 𝑥 = ∀_𝑔 𝑖 ( 1^st ‘ 𝑢 ) ) ) } ) ) , { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑖 ∈ ω ∃ 𝑗 ∈ ω 𝑥 = ( 𝑖 ∈_𝑔 𝑗 ) ) } ) ‘ 𝑁 ) )

Proof

Step	Hyp	Ref	Expression
1		satf0	⊢ ( ∅ Sat ∅ ) = ( rec ( ( 𝑓 ∈ V ↦ ( 𝑓 ∪ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑢 ∈ 𝑓 ( ∃ 𝑣 ∈ 𝑓 𝑥 = ( ( 1^st ‘ 𝑢 ) ⊼_𝑔 ( 1^st ‘ 𝑣 ) ) ∨ ∃ 𝑖 ∈ ω 𝑥 = ∀_𝑔 𝑖 ( 1^st ‘ 𝑢 ) ) ) } ) ) , { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑖 ∈ ω ∃ 𝑗 ∈ ω 𝑥 = ( 𝑖 ∈_𝑔 𝑗 ) ) } ) ↾ suc ω )
2	1	fveq1i	⊢ ( ( ∅ Sat ∅ ) ‘ 𝑁 ) = ( ( rec ( ( 𝑓 ∈ V ↦ ( 𝑓 ∪ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑢 ∈ 𝑓 ( ∃ 𝑣 ∈ 𝑓 𝑥 = ( ( 1^st ‘ 𝑢 ) ⊼_𝑔 ( 1^st ‘ 𝑣 ) ) ∨ ∃ 𝑖 ∈ ω 𝑥 = ∀_𝑔 𝑖 ( 1^st ‘ 𝑢 ) ) ) } ) ) , { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑖 ∈ ω ∃ 𝑗 ∈ ω 𝑥 = ( 𝑖 ∈_𝑔 𝑗 ) ) } ) ↾ suc ω ) ‘ 𝑁 )
3		fvres	⊢ ( 𝑁 ∈ suc ω → ( ( rec ( ( 𝑓 ∈ V ↦ ( 𝑓 ∪ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑢 ∈ 𝑓 ( ∃ 𝑣 ∈ 𝑓 𝑥 = ( ( 1^st ‘ 𝑢 ) ⊼_𝑔 ( 1^st ‘ 𝑣 ) ) ∨ ∃ 𝑖 ∈ ω 𝑥 = ∀_𝑔 𝑖 ( 1^st ‘ 𝑢 ) ) ) } ) ) , { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑖 ∈ ω ∃ 𝑗 ∈ ω 𝑥 = ( 𝑖 ∈_𝑔 𝑗 ) ) } ) ↾ suc ω ) ‘ 𝑁 ) = ( rec ( ( 𝑓 ∈ V ↦ ( 𝑓 ∪ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑢 ∈ 𝑓 ( ∃ 𝑣 ∈ 𝑓 𝑥 = ( ( 1^st ‘ 𝑢 ) ⊼_𝑔 ( 1^st ‘ 𝑣 ) ) ∨ ∃ 𝑖 ∈ ω 𝑥 = ∀_𝑔 𝑖 ( 1^st ‘ 𝑢 ) ) ) } ) ) , { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑖 ∈ ω ∃ 𝑗 ∈ ω 𝑥 = ( 𝑖 ∈_𝑔 𝑗 ) ) } ) ‘ 𝑁 ) )
4	2 3	syl5eq	⊢ ( 𝑁 ∈ suc ω → ( ( ∅ Sat ∅ ) ‘ 𝑁 ) = ( rec ( ( 𝑓 ∈ V ↦ ( 𝑓 ∪ { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑢 ∈ 𝑓 ( ∃ 𝑣 ∈ 𝑓 𝑥 = ( ( 1^st ‘ 𝑢 ) ⊼_𝑔 ( 1^st ‘ 𝑣 ) ) ∨ ∃ 𝑖 ∈ ω 𝑥 = ∀_𝑔 𝑖 ( 1^st ‘ 𝑢 ) ) ) } ) ) , { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( 𝑦 = ∅ ∧ ∃ 𝑖 ∈ ω ∃ 𝑗 ∈ ω 𝑥 = ( 𝑖 ∈_𝑔 𝑗 ) ) } ) ‘ 𝑁 ) )