| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elnn0 | ⊢ ( 𝑀  ∈  ℕ0  ↔  ( 𝑀  ∈  ℕ  ∨  𝑀  =  0 ) ) | 
						
							| 2 |  | n0 | ⊢ ( 𝑅  ≠  ∅  ↔  ∃ 𝑐 𝑐  ∈  𝑅 ) | 
						
							| 3 |  | simpll | ⊢ ( ( ( 𝑀  ∈  ℕ  ∧  𝑅  ∈  𝑉 )  ∧  𝑐  ∈  𝑅 )  →  𝑀  ∈  ℕ ) | 
						
							| 4 |  | simplr | ⊢ ( ( ( 𝑀  ∈  ℕ  ∧  𝑅  ∈  𝑉 )  ∧  𝑐  ∈  𝑅 )  →  𝑅  ∈  𝑉 ) | 
						
							| 5 |  | 0nn0 | ⊢ 0  ∈  ℕ0 | 
						
							| 6 | 5 | fconst6 | ⊢ ( 𝑅  ×  { 0 } ) : 𝑅 ⟶ ℕ0 | 
						
							| 7 | 6 | a1i | ⊢ ( ( ( 𝑀  ∈  ℕ  ∧  𝑅  ∈  𝑉 )  ∧  𝑐  ∈  𝑅 )  →  ( 𝑅  ×  { 0 } ) : 𝑅 ⟶ ℕ0 ) | 
						
							| 8 |  | simpr | ⊢ ( ( ( 𝑀  ∈  ℕ  ∧  𝑅  ∈  𝑉 )  ∧  𝑐  ∈  𝑅 )  →  𝑐  ∈  𝑅 ) | 
						
							| 9 |  | fvconst2g | ⊢ ( ( 0  ∈  ℕ0  ∧  𝑐  ∈  𝑅 )  →  ( ( 𝑅  ×  { 0 } ) ‘ 𝑐 )  =  0 ) | 
						
							| 10 | 5 8 9 | sylancr | ⊢ ( ( ( 𝑀  ∈  ℕ  ∧  𝑅  ∈  𝑉 )  ∧  𝑐  ∈  𝑅 )  →  ( ( 𝑅  ×  { 0 } ) ‘ 𝑐 )  =  0 ) | 
						
							| 11 |  | ramz2 | ⊢ ( ( ( 𝑀  ∈  ℕ  ∧  𝑅  ∈  𝑉  ∧  ( 𝑅  ×  { 0 } ) : 𝑅 ⟶ ℕ0 )  ∧  ( 𝑐  ∈  𝑅  ∧  ( ( 𝑅  ×  { 0 } ) ‘ 𝑐 )  =  0 ) )  →  ( 𝑀  Ramsey  ( 𝑅  ×  { 0 } ) )  =  0 ) | 
						
							| 12 | 3 4 7 8 10 11 | syl32anc | ⊢ ( ( ( 𝑀  ∈  ℕ  ∧  𝑅  ∈  𝑉 )  ∧  𝑐  ∈  𝑅 )  →  ( 𝑀  Ramsey  ( 𝑅  ×  { 0 } ) )  =  0 ) | 
						
							| 13 | 12 | ex | ⊢ ( ( 𝑀  ∈  ℕ  ∧  𝑅  ∈  𝑉 )  →  ( 𝑐  ∈  𝑅  →  ( 𝑀  Ramsey  ( 𝑅  ×  { 0 } ) )  =  0 ) ) | 
						
							| 14 | 13 | exlimdv | ⊢ ( ( 𝑀  ∈  ℕ  ∧  𝑅  ∈  𝑉 )  →  ( ∃ 𝑐 𝑐  ∈  𝑅  →  ( 𝑀  Ramsey  ( 𝑅  ×  { 0 } ) )  =  0 ) ) | 
						
							| 15 | 2 14 | biimtrid | ⊢ ( ( 𝑀  ∈  ℕ  ∧  𝑅  ∈  𝑉 )  →  ( 𝑅  ≠  ∅  →  ( 𝑀  Ramsey  ( 𝑅  ×  { 0 } ) )  =  0 ) ) | 
						
							| 16 | 15 | expimpd | ⊢ ( 𝑀  ∈  ℕ  →  ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ( 𝑀  Ramsey  ( 𝑅  ×  { 0 } ) )  =  0 ) ) | 
						
							| 17 |  | simpl | ⊢ ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  𝑅  ∈  𝑉 ) | 
						
							| 18 |  | simpr | ⊢ ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  𝑅  ≠  ∅ ) | 
						
							| 19 | 6 | a1i | ⊢ ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ( 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 | ⊢ ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ran  ( 𝑅  ×  { 0 } )  =  { 0 } ) | 
						
							| 27 | 26 | raleqdv | ⊢ ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ( ∀ 𝑦  ∈  ran  ( 𝑅  ×  { 0 } ) 𝑦  ≤  0  ↔  ∀ 𝑦  ∈  { 0 } 𝑦  ≤  0 ) ) | 
						
							| 28 | 24 27 | mpbiri | ⊢ ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ∀ 𝑦  ∈  ran  ( 𝑅  ×  { 0 } ) 𝑦  ≤  0 ) | 
						
							| 29 |  | brralrspcev | ⊢ ( ( 0  ∈  ℤ  ∧  ∀ 𝑦  ∈  ran  ( 𝑅  ×  { 0 } ) 𝑦  ≤  0 )  →  ∃ 𝑥  ∈  ℤ ∀ 𝑦  ∈  ran  ( 𝑅  ×  { 0 } ) 𝑦  ≤  𝑥 ) | 
						
							| 30 | 20 28 29 | sylancr | ⊢ ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ∃ 𝑥  ∈  ℤ ∀ 𝑦  ∈  ran  ( 𝑅  ×  { 0 } ) 𝑦  ≤  𝑥 ) | 
						
							| 31 |  | 0ram | ⊢ ( ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅  ∧  ( 𝑅  ×  { 0 } ) : 𝑅 ⟶ ℕ0 )  ∧  ∃ 𝑥  ∈  ℤ ∀ 𝑦  ∈  ran  ( 𝑅  ×  { 0 } ) 𝑦  ≤  𝑥 )  →  ( 0  Ramsey  ( 𝑅  ×  { 0 } ) )  =  sup ( ran  ( 𝑅  ×  { 0 } ) ,  ℝ ,   <  ) ) | 
						
							| 32 | 17 18 19 30 31 | syl31anc | ⊢ ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ( 0  Ramsey  ( 𝑅  ×  { 0 } ) )  =  sup ( ran  ( 𝑅  ×  { 0 } ) ,  ℝ ,   <  ) ) | 
						
							| 33 | 26 | supeq1d | ⊢ ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  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 | ⊢ ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  sup ( { 0 } ,  ℝ ,   <  )  =  0 ) | 
						
							| 39 | 32 33 38 | 3eqtrd | ⊢ ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ( 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 | imbitrrid | ⊢ ( 𝑀  =  0  →  ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ( 𝑀  Ramsey  ( 𝑅  ×  { 0 } ) )  =  0 ) ) | 
						
							| 43 | 16 42 | jaoi | ⊢ ( ( 𝑀  ∈  ℕ  ∨  𝑀  =  0 )  →  ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ( 𝑀  Ramsey  ( 𝑅  ×  { 0 } ) )  =  0 ) ) | 
						
							| 44 | 1 43 | sylbi | ⊢ ( 𝑀  ∈  ℕ0  →  ( ( 𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ( 𝑀  Ramsey  ( 𝑅  ×  { 0 } ) )  =  0 ) ) | 
						
							| 45 | 44 | 3impib | ⊢ ( ( 𝑀  ∈  ℕ0  ∧  𝑅  ∈  𝑉  ∧  𝑅  ≠  ∅ )  →  ( 𝑀  Ramsey  ( 𝑅  ×  { 0 } ) )  =  0 ) |