| Step | Hyp | Ref | Expression | 
						
							| 1 |  | simpl1l | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →  𝐴  ∈   No  ) | 
						
							| 2 |  | simpl3 | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →  𝐶  ∈   No  ) | 
						
							| 3 |  | simpl2 | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →  𝐵  ∈   No  ) | 
						
							| 4 | 2 3 | subscld | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →  ( 𝐶  -s  𝐵 )  ∈   No  ) | 
						
							| 5 |  | simpl1r | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →   0s   <s  𝐴 ) | 
						
							| 6 |  | simp2 | ⊢ ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  𝐵  ∈   No  ) | 
						
							| 7 |  | simp3 | ⊢ ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  𝐶  ∈   No  ) | 
						
							| 8 | 6 7 | posdifsd | ⊢ ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  ( 𝐵  <s  𝐶  ↔   0s   <s  ( 𝐶  -s  𝐵 ) ) ) | 
						
							| 9 | 8 | biimpa | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →   0s   <s  ( 𝐶  -s  𝐵 ) ) | 
						
							| 10 | 1 4 5 9 | mulsgt0d | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →   0s   <s  ( 𝐴  ·s  ( 𝐶  -s  𝐵 ) ) ) | 
						
							| 11 | 1 2 3 | subsdid | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →  ( 𝐴  ·s  ( 𝐶  -s  𝐵 ) )  =  ( ( 𝐴  ·s  𝐶 )  -s  ( 𝐴  ·s  𝐵 ) ) ) | 
						
							| 12 | 10 11 | breqtrd | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →   0s   <s  ( ( 𝐴  ·s  𝐶 )  -s  ( 𝐴  ·s  𝐵 ) ) ) | 
						
							| 13 | 1 3 | mulscld | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →  ( 𝐴  ·s  𝐵 )  ∈   No  ) | 
						
							| 14 | 1 2 | mulscld | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →  ( 𝐴  ·s  𝐶 )  ∈   No  ) | 
						
							| 15 | 13 14 | posdifsd | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →  ( ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 )  ↔   0s   <s  ( ( 𝐴  ·s  𝐶 )  -s  ( 𝐴  ·s  𝐵 ) ) ) ) | 
						
							| 16 | 12 15 | mpbird | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  𝐵  <s  𝐶 )  →  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) ) | 
						
							| 17 |  | simp1l | ⊢ ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  𝐴  ∈   No  ) | 
						
							| 18 | 17 7 | mulscld | ⊢ ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  ( 𝐴  ·s  𝐶 )  ∈   No  ) | 
						
							| 19 |  | sltirr | ⊢ ( ( 𝐴  ·s  𝐶 )  ∈   No   →  ¬  ( 𝐴  ·s  𝐶 )  <s  ( 𝐴  ·s  𝐶 ) ) | 
						
							| 20 | 18 19 | syl | ⊢ ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  ¬  ( 𝐴  ·s  𝐶 )  <s  ( 𝐴  ·s  𝐶 ) ) | 
						
							| 21 |  | oveq2 | ⊢ ( 𝐵  =  𝐶  →  ( 𝐴  ·s  𝐵 )  =  ( 𝐴  ·s  𝐶 ) ) | 
						
							| 22 | 21 | breq1d | ⊢ ( 𝐵  =  𝐶  →  ( ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 )  ↔  ( 𝐴  ·s  𝐶 )  <s  ( 𝐴  ·s  𝐶 ) ) ) | 
						
							| 23 | 22 | notbid | ⊢ ( 𝐵  =  𝐶  →  ( ¬  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 )  ↔  ¬  ( 𝐴  ·s  𝐶 )  <s  ( 𝐴  ·s  𝐶 ) ) ) | 
						
							| 24 | 20 23 | syl5ibrcom | ⊢ ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  ( 𝐵  =  𝐶  →  ¬  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) ) ) | 
						
							| 25 | 24 | con2d | ⊢ ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  ( ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 )  →  ¬  𝐵  =  𝐶 ) ) | 
						
							| 26 | 25 | imp | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  →  ¬  𝐵  =  𝐶 ) | 
						
							| 27 | 17 6 | mulscld | ⊢ ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  ( 𝐴  ·s  𝐵 )  ∈   No  ) | 
						
							| 28 |  | sltasym | ⊢ ( ( ( 𝐴  ·s  𝐵 )  ∈   No   ∧  ( 𝐴  ·s  𝐶 )  ∈   No  )  →  ( ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 )  →  ¬  ( 𝐴  ·s  𝐶 )  <s  ( 𝐴  ·s  𝐵 ) ) ) | 
						
							| 29 | 27 18 28 | syl2anc | ⊢ ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  ( ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 )  →  ¬  ( 𝐴  ·s  𝐶 )  <s  ( 𝐴  ·s  𝐵 ) ) ) | 
						
							| 30 | 29 | imp | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  →  ¬  ( 𝐴  ·s  𝐶 )  <s  ( 𝐴  ·s  𝐵 ) ) | 
						
							| 31 |  | simpl1l | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  →  𝐴  ∈   No  ) | 
						
							| 32 | 31 | adantr | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →  𝐴  ∈   No  ) | 
						
							| 33 |  | simpll2 | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →  𝐵  ∈   No  ) | 
						
							| 34 |  | simpll3 | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →  𝐶  ∈   No  ) | 
						
							| 35 | 33 34 | subscld | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →  ( 𝐵  -s  𝐶 )  ∈   No  ) | 
						
							| 36 |  | simpl1r | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  →   0s   <s  𝐴 ) | 
						
							| 37 | 36 | adantr | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →   0s   <s  𝐴 ) | 
						
							| 38 |  | simpr | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →   0s   <s  ( 𝐵  -s  𝐶 ) ) | 
						
							| 39 | 32 35 37 38 | mulsgt0d | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →   0s   <s  ( 𝐴  ·s  ( 𝐵  -s  𝐶 ) ) ) | 
						
							| 40 | 32 33 34 | subsdid | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →  ( 𝐴  ·s  ( 𝐵  -s  𝐶 ) )  =  ( ( 𝐴  ·s  𝐵 )  -s  ( 𝐴  ·s  𝐶 ) ) ) | 
						
							| 41 | 40 | breq2d | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →  (  0s   <s  ( 𝐴  ·s  ( 𝐵  -s  𝐶 ) )  ↔   0s   <s  ( ( 𝐴  ·s  𝐵 )  -s  ( 𝐴  ·s  𝐶 ) ) ) ) | 
						
							| 42 | 18 | ad2antrr | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →  ( 𝐴  ·s  𝐶 )  ∈   No  ) | 
						
							| 43 | 27 | ad2antrr | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →  ( 𝐴  ·s  𝐵 )  ∈   No  ) | 
						
							| 44 | 42 43 | posdifsd | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →  ( ( 𝐴  ·s  𝐶 )  <s  ( 𝐴  ·s  𝐵 )  ↔   0s   <s  ( ( 𝐴  ·s  𝐵 )  -s  ( 𝐴  ·s  𝐶 ) ) ) ) | 
						
							| 45 | 41 44 | bitr4d | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →  (  0s   <s  ( 𝐴  ·s  ( 𝐵  -s  𝐶 ) )  ↔  ( 𝐴  ·s  𝐶 )  <s  ( 𝐴  ·s  𝐵 ) ) ) | 
						
							| 46 | 39 45 | mpbid | ⊢ ( ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  ∧   0s   <s  ( 𝐵  -s  𝐶 ) )  →  ( 𝐴  ·s  𝐶 )  <s  ( 𝐴  ·s  𝐵 ) ) | 
						
							| 47 | 30 46 | mtand | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  →  ¬   0s   <s  ( 𝐵  -s  𝐶 ) ) | 
						
							| 48 |  | simpl3 | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  →  𝐶  ∈   No  ) | 
						
							| 49 |  | simpl2 | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  →  𝐵  ∈   No  ) | 
						
							| 50 | 48 49 | posdifsd | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  →  ( 𝐶  <s  𝐵  ↔   0s   <s  ( 𝐵  -s  𝐶 ) ) ) | 
						
							| 51 | 47 50 | mtbird | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  →  ¬  𝐶  <s  𝐵 ) | 
						
							| 52 |  | sltlin | ⊢ ( ( 𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  ( 𝐵  <s  𝐶  ∨  𝐵  =  𝐶  ∨  𝐶  <s  𝐵 ) ) | 
						
							| 53 | 49 48 52 | syl2anc | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  →  ( 𝐵  <s  𝐶  ∨  𝐵  =  𝐶  ∨  𝐶  <s  𝐵 ) ) | 
						
							| 54 | 26 51 53 | ecase23d | ⊢ ( ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  ∧  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) )  →  𝐵  <s  𝐶 ) | 
						
							| 55 | 16 54 | impbida | ⊢ ( ( ( 𝐴  ∈   No   ∧   0s   <s  𝐴 )  ∧  𝐵  ∈   No   ∧  𝐶  ∈   No  )  →  ( 𝐵  <s  𝐶  ↔  ( 𝐴  ·s  𝐵 )  <s  ( 𝐴  ·s  𝐶 ) ) ) |