Description: A more general version of axdc3 that allows the function F to vary with k . (Contributed by Mario Carneiro, 31-Jan-2013)
Ref | Expression | ||
---|---|---|---|
Hypothesis | axdc4.1 | ⊢ 𝐴 ∈ V | |
Assertion | axdc4 | ⊢ ( ( 𝐶 ∈ 𝐴 ∧ 𝐹 : ( ω × 𝐴 ) ⟶ ( 𝒫 𝐴 ∖ { ∅ } ) ) → ∃ 𝑔 ( 𝑔 : ω ⟶ 𝐴 ∧ ( 𝑔 ‘ ∅ ) = 𝐶 ∧ ∀ 𝑘 ∈ ω ( 𝑔 ‘ suc 𝑘 ) ∈ ( 𝑘 𝐹 ( 𝑔 ‘ 𝑘 ) ) ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | axdc4.1 | ⊢ 𝐴 ∈ V | |
2 | eqid | ⊢ ( 𝑛 ∈ ω , 𝑥 ∈ 𝐴 ↦ ( { suc 𝑛 } × ( 𝑛 𝐹 𝑥 ) ) ) = ( 𝑛 ∈ ω , 𝑥 ∈ 𝐴 ↦ ( { suc 𝑛 } × ( 𝑛 𝐹 𝑥 ) ) ) | |
3 | 1 2 | axdc4lem | ⊢ ( ( 𝐶 ∈ 𝐴 ∧ 𝐹 : ( ω × 𝐴 ) ⟶ ( 𝒫 𝐴 ∖ { ∅ } ) ) → ∃ 𝑔 ( 𝑔 : ω ⟶ 𝐴 ∧ ( 𝑔 ‘ ∅ ) = 𝐶 ∧ ∀ 𝑘 ∈ ω ( 𝑔 ‘ suc 𝑘 ) ∈ ( 𝑘 𝐹 ( 𝑔 ‘ 𝑘 ) ) ) ) |