Metamath Proof Explorer


Theorem madef

Description: The made function is a function from ordinals to sets of surreals. (Contributed by Scott Fenton, 6-Aug-2024)

Ref Expression
Assertion madef M : On ⟶ 𝒫 No

Proof

Step Hyp Ref Expression
1 df-made ⊢ M = recs ( ( 𝑥 ∈ V ↦ ( |s “ ( 𝒫 ∪ ran 𝑥 × 𝒫 ∪ ran 𝑥 ) ) ) )
2 1 tfr1 ⊢ M Fn On
3 madeval2 ⊢ ( 𝑥 ∈ On → ( M ‘ 𝑥 ) = { 𝑦 ∈ No ∣ ∃ 𝑧 ∈ 𝒫 ∪ ( M “ 𝑥 ) ∃ 𝑤 ∈ 𝒫 ∪ ( M “ 𝑥 ) ( 𝑧 <<s 𝑤 ∧ ( 𝑧 |s 𝑤 ) = 𝑦 ) } )
4 ssrab2 ⊢ { 𝑦 ∈ No ∣ ∃ 𝑧 ∈ 𝒫 ∪ ( M “ 𝑥 ) ∃ 𝑤 ∈ 𝒫 ∪ ( M “ 𝑥 ) ( 𝑧 <<s 𝑤 ∧ ( 𝑧 |s 𝑤 ) = 𝑦 ) } ⊆ No
5 3 4 eqsstrdi ⊢ ( 𝑥 ∈ On → ( M ‘ 𝑥 ) ⊆ No )
6 sseq1 ⊢ ( 𝑦 = ( M ‘ 𝑥 ) → ( 𝑦 ⊆ No ↔ ( M ‘ 𝑥 ) ⊆ No ) )
7 5 6 syl5ibrcom ⊢ ( 𝑥 ∈ On → ( 𝑦 = ( M ‘ 𝑥 ) → 𝑦 ⊆ No ) )
8 7 rexlimiv ⊢ ( ∃ 𝑥 ∈ On 𝑦 = ( M ‘ 𝑥 ) → 𝑦 ⊆ No )
9 vex ⊢ 𝑦 ∈ V
10 eqeq1 ⊢ ( 𝑧 = 𝑦 → ( 𝑧 = ( M ‘ 𝑥 ) ↔ 𝑦 = ( M ‘ 𝑥 ) ) )
11 10 rexbidv ⊢ ( 𝑧 = 𝑦 → ( ∃ 𝑥 ∈ On 𝑧 = ( M ‘ 𝑥 ) ↔ ∃ 𝑥 ∈ On 𝑦 = ( M ‘ 𝑥 ) ) )
12 fnrnfv ⊢ ( M Fn On → ran M = { 𝑧 ∣ ∃ 𝑥 ∈ On 𝑧 = ( M ‘ 𝑥 ) } )
13 2 12 ax-mp ⊢ ran M = { 𝑧 ∣ ∃ 𝑥 ∈ On 𝑧 = ( M ‘ 𝑥 ) }
14 9 11 13 elab2 ⊢ ( 𝑦 ∈ ran M ↔ ∃ 𝑥 ∈ On 𝑦 = ( M ‘ 𝑥 ) )
15 velpw ⊢ ( 𝑦 ∈ 𝒫 No ↔ 𝑦 ⊆ No )
16 8 14 15 3imtr4i ⊢ ( 𝑦 ∈ ran M → 𝑦 ∈ 𝒫 No )
17 16 ssriv ⊢ ran M ⊆ 𝒫 No
18 df-f ⊢ ( M : On ⟶ 𝒫 No ↔ ( M Fn On ∧ ran M ⊆ 𝒫 No ) )
19 2 17 18 mpbir2an ⊢ M : On ⟶ 𝒫 No