Metamath Proof Explorer


Theorem ramz

Description: The Ramsey number when F is the zero function. (Contributed by Mario Carneiro, 22-Apr-2015)

Ref Expression
Assertion ramz ( ( 𝑀 ∈ ℕ0𝑅𝑉𝑅 ≠ ∅ ) → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 )

Proof

Step Hyp Ref Expression
1 elnn0 ( 𝑀 ∈ ℕ0 ↔ ( 𝑀 ∈ ℕ ∨ 𝑀 = 0 ) )
2 n0 ( 𝑅 ≠ ∅ ↔ ∃ 𝑐 𝑐𝑅 )
3 simpll ( ( ( 𝑀 ∈ ℕ ∧ 𝑅𝑉 ) ∧ 𝑐𝑅 ) → 𝑀 ∈ ℕ )
4 simplr ( ( ( 𝑀 ∈ ℕ ∧ 𝑅𝑉 ) ∧ 𝑐𝑅 ) → 𝑅𝑉 )
5 0nn0 0 ∈ ℕ0
6 5 fconst6 ( 𝑅 × { 0 } ) : 𝑅 ⟶ ℕ0
7 6 a1i ( ( ( 𝑀 ∈ ℕ ∧ 𝑅𝑉 ) ∧ 𝑐𝑅 ) → ( 𝑅 × { 0 } ) : 𝑅 ⟶ ℕ0 )
8 simpr ( ( ( 𝑀 ∈ ℕ ∧ 𝑅𝑉 ) ∧ 𝑐𝑅 ) → 𝑐𝑅 )
9 fvconst2g ( ( 0 ∈ ℕ0𝑐𝑅 ) → ( ( 𝑅 × { 0 } ) ‘ 𝑐 ) = 0 )
10 5 8 9 sylancr ( ( ( 𝑀 ∈ ℕ ∧ 𝑅𝑉 ) ∧ 𝑐𝑅 ) → ( ( 𝑅 × { 0 } ) ‘ 𝑐 ) = 0 )
11 ramz2 ( ( ( 𝑀 ∈ ℕ ∧ 𝑅𝑉 ∧ ( 𝑅 × { 0 } ) : 𝑅 ⟶ ℕ0 ) ∧ ( 𝑐𝑅 ∧ ( ( 𝑅 × { 0 } ) ‘ 𝑐 ) = 0 ) ) → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 )
12 3 4 7 8 10 11 syl32anc ( ( ( 𝑀 ∈ ℕ ∧ 𝑅𝑉 ) ∧ 𝑐𝑅 ) → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 )
13 12 ex ( ( 𝑀 ∈ ℕ ∧ 𝑅𝑉 ) → ( 𝑐𝑅 → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 ) )
14 13 exlimdv ( ( 𝑀 ∈ ℕ ∧ 𝑅𝑉 ) → ( ∃ 𝑐 𝑐𝑅 → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 ) )
15 2 14 syl5bi ( ( 𝑀 ∈ ℕ ∧ 𝑅𝑉 ) → ( 𝑅 ≠ ∅ → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 ) )
16 15 expimpd ( 𝑀 ∈ ℕ → ( ( 𝑅𝑉𝑅 ≠ ∅ ) → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 ) )
17 simpl ( ( 𝑅𝑉𝑅 ≠ ∅ ) → 𝑅𝑉 )
18 simpr ( ( 𝑅𝑉𝑅 ≠ ∅ ) → 𝑅 ≠ ∅ )
19 6 a1i ( ( 𝑅𝑉𝑅 ≠ ∅ ) → ( 𝑅 × { 0 } ) : 𝑅 ⟶ ℕ0 )
20 0z 0 ∈ ℤ
21 elsni ( 𝑦 ∈ { 0 } → 𝑦 = 0 )
22 0le0 0 ≤ 0
23 21 22 eqbrtrdi ( 𝑦 ∈ { 0 } → 𝑦 ≤ 0 )
24 23 rgen 𝑦 ∈ { 0 } 𝑦 ≤ 0
25 rnxp ( 𝑅 ≠ ∅ → ran ( 𝑅 × { 0 } ) = { 0 } )
26 25 adantl ( ( 𝑅𝑉𝑅 ≠ ∅ ) → ran ( 𝑅 × { 0 } ) = { 0 } )
27 26 raleqdv ( ( 𝑅𝑉𝑅 ≠ ∅ ) → ( ∀ 𝑦 ∈ ran ( 𝑅 × { 0 } ) 𝑦 ≤ 0 ↔ ∀ 𝑦 ∈ { 0 } 𝑦 ≤ 0 ) )
28 24 27 mpbiri ( ( 𝑅𝑉𝑅 ≠ ∅ ) → ∀ 𝑦 ∈ ran ( 𝑅 × { 0 } ) 𝑦 ≤ 0 )
29 brralrspcev ( ( 0 ∈ ℤ ∧ ∀ 𝑦 ∈ ran ( 𝑅 × { 0 } ) 𝑦 ≤ 0 ) → ∃ 𝑥 ∈ ℤ ∀ 𝑦 ∈ ran ( 𝑅 × { 0 } ) 𝑦𝑥 )
30 20 28 29 sylancr ( ( 𝑅𝑉𝑅 ≠ ∅ ) → ∃ 𝑥 ∈ ℤ ∀ 𝑦 ∈ ran ( 𝑅 × { 0 } ) 𝑦𝑥 )
31 0ram ( ( ( 𝑅𝑉𝑅 ≠ ∅ ∧ ( 𝑅 × { 0 } ) : 𝑅 ⟶ ℕ0 ) ∧ ∃ 𝑥 ∈ ℤ ∀ 𝑦 ∈ ran ( 𝑅 × { 0 } ) 𝑦𝑥 ) → ( 0 Ramsey ( 𝑅 × { 0 } ) ) = sup ( ran ( 𝑅 × { 0 } ) , ℝ , < ) )
32 17 18 19 30 31 syl31anc ( ( 𝑅𝑉𝑅 ≠ ∅ ) → ( 0 Ramsey ( 𝑅 × { 0 } ) ) = sup ( ran ( 𝑅 × { 0 } ) , ℝ , < ) )
33 26 supeq1d ( ( 𝑅𝑉𝑅 ≠ ∅ ) → sup ( ran ( 𝑅 × { 0 } ) , ℝ , < ) = sup ( { 0 } , ℝ , < ) )
34 ltso < Or ℝ
35 0re 0 ∈ ℝ
36 supsn ( ( < Or ℝ ∧ 0 ∈ ℝ ) → sup ( { 0 } , ℝ , < ) = 0 )
37 34 35 36 mp2an sup ( { 0 } , ℝ , < ) = 0
38 37 a1i ( ( 𝑅𝑉𝑅 ≠ ∅ ) → sup ( { 0 } , ℝ , < ) = 0 )
39 32 33 38 3eqtrd ( ( 𝑅𝑉𝑅 ≠ ∅ ) → ( 0 Ramsey ( 𝑅 × { 0 } ) ) = 0 )
40 oveq1 ( 𝑀 = 0 → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = ( 0 Ramsey ( 𝑅 × { 0 } ) ) )
41 40 eqeq1d ( 𝑀 = 0 → ( ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 ↔ ( 0 Ramsey ( 𝑅 × { 0 } ) ) = 0 ) )
42 39 41 syl5ibr ( 𝑀 = 0 → ( ( 𝑅𝑉𝑅 ≠ ∅ ) → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 ) )
43 16 42 jaoi ( ( 𝑀 ∈ ℕ ∨ 𝑀 = 0 ) → ( ( 𝑅𝑉𝑅 ≠ ∅ ) → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 ) )
44 1 43 sylbi ( 𝑀 ∈ ℕ0 → ( ( 𝑅𝑉𝑅 ≠ ∅ ) → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 ) )
45 44 3impib ( ( 𝑀 ∈ ℕ0𝑅𝑉𝑅 ≠ ∅ ) → ( 𝑀 Ramsey ( 𝑅 × { 0 } ) ) = 0 )