Metamath Proof Explorer


Theorem bdayfinbndcbv

Description: Lemma for bdayfinbnd . Change some bound variables. (Contributed by Scott Fenton, 25-Feb-2026)

Ref Expression
Hypotheses bdayfinbndlem.1 ( 𝜑𝑁 ∈ ℕ0s )
bdayfinbndlem.2 ( 𝜑 → ∀ 𝑧 No ( ( ( bday 𝑧 ) ⊆ ( bday 𝑁 ) ∧ 0s ≤s 𝑧 ) → ( 𝑧 = 𝑁 ∨ ∃ 𝑥 ∈ ℕ0s𝑦 ∈ ℕ0s𝑝 ∈ ℕ0s ( 𝑧 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ) ) )
Assertion bdayfinbndcbv ( 𝜑 → ∀ 𝑤 No ( ( ( bday 𝑤 ) ⊆ ( bday 𝑁 ) ∧ 0s ≤s 𝑤 ) → ( 𝑤 = 𝑁 ∨ ∃ 𝑎 ∈ ℕ0s𝑏 ∈ ℕ0s𝑞 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) ∧ 𝑏 <s ( 2ss 𝑞 ) ∧ ( 𝑎 +s 𝑞 ) <s 𝑁 ) ) ) )

Proof

Step Hyp Ref Expression
1 bdayfinbndlem.1 ( 𝜑𝑁 ∈ ℕ0s )
2 bdayfinbndlem.2 ( 𝜑 → ∀ 𝑧 No ( ( ( bday 𝑧 ) ⊆ ( bday 𝑁 ) ∧ 0s ≤s 𝑧 ) → ( 𝑧 = 𝑁 ∨ ∃ 𝑥 ∈ ℕ0s𝑦 ∈ ℕ0s𝑝 ∈ ℕ0s ( 𝑧 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ) ) )
3 fveq2 ( 𝑧 = 𝑤 → ( bday 𝑧 ) = ( bday 𝑤 ) )
4 3 sseq1d ( 𝑧 = 𝑤 → ( ( bday 𝑧 ) ⊆ ( bday 𝑁 ) ↔ ( bday 𝑤 ) ⊆ ( bday 𝑁 ) ) )
5 breq2 ( 𝑧 = 𝑤 → ( 0s ≤s 𝑧 ↔ 0s ≤s 𝑤 ) )
6 4 5 anbi12d ( 𝑧 = 𝑤 → ( ( ( bday 𝑧 ) ⊆ ( bday 𝑁 ) ∧ 0s ≤s 𝑧 ) ↔ ( ( bday 𝑤 ) ⊆ ( bday 𝑁 ) ∧ 0s ≤s 𝑤 ) ) )
7 eqeq1 ( 𝑧 = 𝑤 → ( 𝑧 = 𝑁𝑤 = 𝑁 ) )
8 eqeq1 ( 𝑧 = 𝑤 → ( 𝑧 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ↔ 𝑤 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ) )
9 8 3anbi1d ( 𝑧 = 𝑤 → ( ( 𝑧 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ↔ ( 𝑤 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ) )
10 9 rexbidv ( 𝑧 = 𝑤 → ( ∃ 𝑝 ∈ ℕ0s ( 𝑧 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ↔ ∃ 𝑝 ∈ ℕ0s ( 𝑤 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ) )
11 10 2rexbidv ( 𝑧 = 𝑤 → ( ∃ 𝑥 ∈ ℕ0s𝑦 ∈ ℕ0s𝑝 ∈ ℕ0s ( 𝑧 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ↔ ∃ 𝑥 ∈ ℕ0s𝑦 ∈ ℕ0s𝑝 ∈ ℕ0s ( 𝑤 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ) )
12 oveq1 ( 𝑥 = 𝑎 → ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) = ( 𝑎 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) )
13 12 eqeq2d ( 𝑥 = 𝑎 → ( 𝑤 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ↔ 𝑤 = ( 𝑎 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ) )
14 oveq1 ( 𝑥 = 𝑎 → ( 𝑥 +s 𝑝 ) = ( 𝑎 +s 𝑝 ) )
15 14 breq1d ( 𝑥 = 𝑎 → ( ( 𝑥 +s 𝑝 ) <s 𝑁 ↔ ( 𝑎 +s 𝑝 ) <s 𝑁 ) )
16 13 15 3anbi13d ( 𝑥 = 𝑎 → ( ( 𝑤 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ↔ ( 𝑤 = ( 𝑎 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑎 +s 𝑝 ) <s 𝑁 ) ) )
17 16 rexbidv ( 𝑥 = 𝑎 → ( ∃ 𝑝 ∈ ℕ0s ( 𝑤 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ↔ ∃ 𝑝 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑎 +s 𝑝 ) <s 𝑁 ) ) )
18 oveq1 ( 𝑦 = 𝑏 → ( 𝑦 /su ( 2ss 𝑝 ) ) = ( 𝑏 /su ( 2ss 𝑝 ) ) )
19 18 oveq2d ( 𝑦 = 𝑏 → ( 𝑎 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑝 ) ) ) )
20 19 eqeq2d ( 𝑦 = 𝑏 → ( 𝑤 = ( 𝑎 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ↔ 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑝 ) ) ) ) )
21 breq1 ( 𝑦 = 𝑏 → ( 𝑦 <s ( 2ss 𝑝 ) ↔ 𝑏 <s ( 2ss 𝑝 ) ) )
22 20 21 3anbi12d ( 𝑦 = 𝑏 → ( ( 𝑤 = ( 𝑎 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑎 +s 𝑝 ) <s 𝑁 ) ↔ ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑝 ) ) ) ∧ 𝑏 <s ( 2ss 𝑝 ) ∧ ( 𝑎 +s 𝑝 ) <s 𝑁 ) ) )
23 22 rexbidv ( 𝑦 = 𝑏 → ( ∃ 𝑝 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑎 +s 𝑝 ) <s 𝑁 ) ↔ ∃ 𝑝 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑝 ) ) ) ∧ 𝑏 <s ( 2ss 𝑝 ) ∧ ( 𝑎 +s 𝑝 ) <s 𝑁 ) ) )
24 oveq2 ( 𝑝 = 𝑞 → ( 2ss 𝑝 ) = ( 2ss 𝑞 ) )
25 oveq2 ( ( 2ss 𝑝 ) = ( 2ss 𝑞 ) → ( 𝑏 /su ( 2ss 𝑝 ) ) = ( 𝑏 /su ( 2ss 𝑞 ) ) )
26 24 25 syl ( 𝑝 = 𝑞 → ( 𝑏 /su ( 2ss 𝑝 ) ) = ( 𝑏 /su ( 2ss 𝑞 ) ) )
27 26 oveq2d ( 𝑝 = 𝑞 → ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑝 ) ) ) = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) )
28 27 eqeq2d ( 𝑝 = 𝑞 → ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑝 ) ) ) ↔ 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) ) )
29 24 breq2d ( 𝑝 = 𝑞 → ( 𝑏 <s ( 2ss 𝑝 ) ↔ 𝑏 <s ( 2ss 𝑞 ) ) )
30 oveq2 ( 𝑝 = 𝑞 → ( 𝑎 +s 𝑝 ) = ( 𝑎 +s 𝑞 ) )
31 30 breq1d ( 𝑝 = 𝑞 → ( ( 𝑎 +s 𝑝 ) <s 𝑁 ↔ ( 𝑎 +s 𝑞 ) <s 𝑁 ) )
32 28 29 31 3anbi123d ( 𝑝 = 𝑞 → ( ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑝 ) ) ) ∧ 𝑏 <s ( 2ss 𝑝 ) ∧ ( 𝑎 +s 𝑝 ) <s 𝑁 ) ↔ ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) ∧ 𝑏 <s ( 2ss 𝑞 ) ∧ ( 𝑎 +s 𝑞 ) <s 𝑁 ) ) )
33 32 cbvrexvw ( ∃ 𝑝 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑝 ) ) ) ∧ 𝑏 <s ( 2ss 𝑝 ) ∧ ( 𝑎 +s 𝑝 ) <s 𝑁 ) ↔ ∃ 𝑞 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) ∧ 𝑏 <s ( 2ss 𝑞 ) ∧ ( 𝑎 +s 𝑞 ) <s 𝑁 ) )
34 23 33 bitrdi ( 𝑦 = 𝑏 → ( ∃ 𝑝 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑎 +s 𝑝 ) <s 𝑁 ) ↔ ∃ 𝑞 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) ∧ 𝑏 <s ( 2ss 𝑞 ) ∧ ( 𝑎 +s 𝑞 ) <s 𝑁 ) ) )
35 17 34 cbvrex2vw ( ∃ 𝑥 ∈ ℕ0s𝑦 ∈ ℕ0s𝑝 ∈ ℕ0s ( 𝑤 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ↔ ∃ 𝑎 ∈ ℕ0s𝑏 ∈ ℕ0s𝑞 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) ∧ 𝑏 <s ( 2ss 𝑞 ) ∧ ( 𝑎 +s 𝑞 ) <s 𝑁 ) )
36 11 35 bitrdi ( 𝑧 = 𝑤 → ( ∃ 𝑥 ∈ ℕ0s𝑦 ∈ ℕ0s𝑝 ∈ ℕ0s ( 𝑧 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ↔ ∃ 𝑎 ∈ ℕ0s𝑏 ∈ ℕ0s𝑞 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) ∧ 𝑏 <s ( 2ss 𝑞 ) ∧ ( 𝑎 +s 𝑞 ) <s 𝑁 ) ) )
37 7 36 orbi12d ( 𝑧 = 𝑤 → ( ( 𝑧 = 𝑁 ∨ ∃ 𝑥 ∈ ℕ0s𝑦 ∈ ℕ0s𝑝 ∈ ℕ0s ( 𝑧 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ) ↔ ( 𝑤 = 𝑁 ∨ ∃ 𝑎 ∈ ℕ0s𝑏 ∈ ℕ0s𝑞 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) ∧ 𝑏 <s ( 2ss 𝑞 ) ∧ ( 𝑎 +s 𝑞 ) <s 𝑁 ) ) ) )
38 6 37 imbi12d ( 𝑧 = 𝑤 → ( ( ( ( bday 𝑧 ) ⊆ ( bday 𝑁 ) ∧ 0s ≤s 𝑧 ) → ( 𝑧 = 𝑁 ∨ ∃ 𝑥 ∈ ℕ0s𝑦 ∈ ℕ0s𝑝 ∈ ℕ0s ( 𝑧 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ) ) ↔ ( ( ( bday 𝑤 ) ⊆ ( bday 𝑁 ) ∧ 0s ≤s 𝑤 ) → ( 𝑤 = 𝑁 ∨ ∃ 𝑎 ∈ ℕ0s𝑏 ∈ ℕ0s𝑞 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) ∧ 𝑏 <s ( 2ss 𝑞 ) ∧ ( 𝑎 +s 𝑞 ) <s 𝑁 ) ) ) ) )
39 38 cbvralvw ( ∀ 𝑧 No ( ( ( bday 𝑧 ) ⊆ ( bday 𝑁 ) ∧ 0s ≤s 𝑧 ) → ( 𝑧 = 𝑁 ∨ ∃ 𝑥 ∈ ℕ0s𝑦 ∈ ℕ0s𝑝 ∈ ℕ0s ( 𝑧 = ( 𝑥 +s ( 𝑦 /su ( 2ss 𝑝 ) ) ) ∧ 𝑦 <s ( 2ss 𝑝 ) ∧ ( 𝑥 +s 𝑝 ) <s 𝑁 ) ) ) ↔ ∀ 𝑤 No ( ( ( bday 𝑤 ) ⊆ ( bday 𝑁 ) ∧ 0s ≤s 𝑤 ) → ( 𝑤 = 𝑁 ∨ ∃ 𝑎 ∈ ℕ0s𝑏 ∈ ℕ0s𝑞 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) ∧ 𝑏 <s ( 2ss 𝑞 ) ∧ ( 𝑎 +s 𝑞 ) <s 𝑁 ) ) ) )
40 2 39 sylib ( 𝜑 → ∀ 𝑤 No ( ( ( bday 𝑤 ) ⊆ ( bday 𝑁 ) ∧ 0s ≤s 𝑤 ) → ( 𝑤 = 𝑁 ∨ ∃ 𝑎 ∈ ℕ0s𝑏 ∈ ℕ0s𝑞 ∈ ℕ0s ( 𝑤 = ( 𝑎 +s ( 𝑏 /su ( 2ss 𝑞 ) ) ) ∧ 𝑏 <s ( 2ss 𝑞 ) ∧ ( 𝑎 +s 𝑞 ) <s 𝑁 ) ) ) )