| Step | Hyp | Ref | Expression | 
						
							| 1 |  | oveq2 | ⊢ ( 𝑛  =  ( 𝑝  ·s  𝑞 )  →  (  1s   /su  𝑛 )  =  (  1s   /su  ( 𝑝  ·s  𝑞 ) ) ) | 
						
							| 2 | 1 | oveq2d | ⊢ ( 𝑛  =  ( 𝑝  ·s  𝑞 )  →  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 (  1s   /su  ( 𝑝  ·s  𝑞 ) ) ) ) | 
						
							| 3 | 2 | eqeq2d | ⊢ ( 𝑛  =  ( 𝑝  ·s  𝑞 )  →  ( ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  ↔  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  =  ( 𝐵 𝐹 (  1s   /su  ( 𝑝  ·s  𝑞 ) ) ) ) ) | 
						
							| 4 |  | nnmulscl | ⊢ ( ( 𝑝  ∈  ℕs  ∧  𝑞  ∈  ℕs )  →  ( 𝑝  ·s  𝑞 )  ∈  ℕs ) | 
						
							| 5 |  | 1sno | ⊢  1s   ∈   No | 
						
							| 6 | 5 | a1i | ⊢ ( ( 𝑝  ∈  ℕs  ∧  𝑞  ∈  ℕs )  →   1s   ∈   No  ) | 
						
							| 7 |  | nnsno | ⊢ ( 𝑝  ∈  ℕs  →  𝑝  ∈   No  ) | 
						
							| 8 | 7 | adantr | ⊢ ( ( 𝑝  ∈  ℕs  ∧  𝑞  ∈  ℕs )  →  𝑝  ∈   No  ) | 
						
							| 9 |  | nnsno | ⊢ ( 𝑞  ∈  ℕs  →  𝑞  ∈   No  ) | 
						
							| 10 | 9 | adantl | ⊢ ( ( 𝑝  ∈  ℕs  ∧  𝑞  ∈  ℕs )  →  𝑞  ∈   No  ) | 
						
							| 11 |  | nnne0s | ⊢ ( 𝑝  ∈  ℕs  →  𝑝  ≠   0s  ) | 
						
							| 12 | 11 | adantr | ⊢ ( ( 𝑝  ∈  ℕs  ∧  𝑞  ∈  ℕs )  →  𝑝  ≠   0s  ) | 
						
							| 13 |  | nnne0s | ⊢ ( 𝑞  ∈  ℕs  →  𝑞  ≠   0s  ) | 
						
							| 14 | 13 | adantl | ⊢ ( ( 𝑝  ∈  ℕs  ∧  𝑞  ∈  ℕs )  →  𝑞  ≠   0s  ) | 
						
							| 15 | 6 8 6 10 12 14 | divmuldivsd | ⊢ ( ( 𝑝  ∈  ℕs  ∧  𝑞  ∈  ℕs )  →  ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) )  =  ( (  1s   ·s   1s  )  /su  ( 𝑝  ·s  𝑞 ) ) ) | 
						
							| 16 |  | mulsrid | ⊢ (  1s   ∈   No   →  (  1s   ·s   1s  )  =   1s  ) | 
						
							| 17 | 5 16 | ax-mp | ⊢ (  1s   ·s   1s  )  =   1s | 
						
							| 18 | 17 | oveq1i | ⊢ ( (  1s   ·s   1s  )  /su  ( 𝑝  ·s  𝑞 ) )  =  (  1s   /su  ( 𝑝  ·s  𝑞 ) ) | 
						
							| 19 | 15 18 | eqtrdi | ⊢ ( ( 𝑝  ∈  ℕs  ∧  𝑞  ∈  ℕs )  →  ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) )  =  (  1s   /su  ( 𝑝  ·s  𝑞 ) ) ) | 
						
							| 20 | 19 | oveq2d | ⊢ ( ( 𝑝  ∈  ℕs  ∧  𝑞  ∈  ℕs )  →  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  =  ( 𝐵 𝐹 (  1s   /su  ( 𝑝  ·s  𝑞 ) ) ) ) | 
						
							| 21 | 3 4 20 | rspcedvdw | ⊢ ( ( 𝑝  ∈  ℕs  ∧  𝑞  ∈  ℕs )  →  ∃ 𝑛  ∈  ℕs ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) ) ) | 
						
							| 22 |  | eqeq1 | ⊢ ( 𝐴  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  →  ( 𝐴  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  ↔  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) ) ) ) | 
						
							| 23 | 22 | rexbidv | ⊢ ( 𝐴  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  →  ( ∃ 𝑛  ∈  ℕs 𝐴  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  ↔  ∃ 𝑛  ∈  ℕs ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) ) ) ) | 
						
							| 24 | 21 23 | syl5ibrcom | ⊢ ( ( 𝑝  ∈  ℕs  ∧  𝑞  ∈  ℕs )  →  ( 𝐴  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  →  ∃ 𝑛  ∈  ℕs 𝐴  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) ) ) ) | 
						
							| 25 | 24 | rexlimivv | ⊢ ( ∃ 𝑝  ∈  ℕs ∃ 𝑞  ∈  ℕs 𝐴  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  →  ∃ 𝑛  ∈  ℕs 𝐴  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) ) ) | 
						
							| 26 | 5 | a1i | ⊢ ( 𝑛  ∈  ℕs  →   1s   ∈   No  ) | 
						
							| 27 |  | nnsno | ⊢ ( 𝑛  ∈  ℕs  →  𝑛  ∈   No  ) | 
						
							| 28 |  | nnne0s | ⊢ ( 𝑛  ∈  ℕs  →  𝑛  ≠   0s  ) | 
						
							| 29 | 26 27 28 | divscld | ⊢ ( 𝑛  ∈  ℕs  →  (  1s   /su  𝑛 )  ∈   No  ) | 
						
							| 30 | 29 | mulsridd | ⊢ ( 𝑛  ∈  ℕs  →  ( (  1s   /su  𝑛 )  ·s   1s  )  =  (  1s   /su  𝑛 ) ) | 
						
							| 31 | 30 | eqcomd | ⊢ ( 𝑛  ∈  ℕs  →  (  1s   /su  𝑛 )  =  ( (  1s   /su  𝑛 )  ·s   1s  ) ) | 
						
							| 32 | 31 | oveq2d | ⊢ ( 𝑛  ∈  ℕs  →  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑛 )  ·s   1s  ) ) ) | 
						
							| 33 |  | 1nns | ⊢  1s   ∈  ℕs | 
						
							| 34 |  | oveq2 | ⊢ ( 𝑝  =  𝑛  →  (  1s   /su  𝑝 )  =  (  1s   /su  𝑛 ) ) | 
						
							| 35 | 34 | oveq1d | ⊢ ( 𝑝  =  𝑛  →  ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) )  =  ( (  1s   /su  𝑛 )  ·s  (  1s   /su  𝑞 ) ) ) | 
						
							| 36 | 35 | oveq2d | ⊢ ( 𝑝  =  𝑛  →  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑛 )  ·s  (  1s   /su  𝑞 ) ) ) ) | 
						
							| 37 | 36 | eqeq2d | ⊢ ( 𝑝  =  𝑛  →  ( ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  ↔  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑛 )  ·s  (  1s   /su  𝑞 ) ) ) ) ) | 
						
							| 38 |  | oveq2 | ⊢ ( 𝑞  =   1s   →  (  1s   /su  𝑞 )  =  (  1s   /su   1s  ) ) | 
						
							| 39 |  | divs1 | ⊢ (  1s   ∈   No   →  (  1s   /su   1s  )  =   1s  ) | 
						
							| 40 | 5 39 | ax-mp | ⊢ (  1s   /su   1s  )  =   1s | 
						
							| 41 | 38 40 | eqtrdi | ⊢ ( 𝑞  =   1s   →  (  1s   /su  𝑞 )  =   1s  ) | 
						
							| 42 | 41 | oveq2d | ⊢ ( 𝑞  =   1s   →  ( (  1s   /su  𝑛 )  ·s  (  1s   /su  𝑞 ) )  =  ( (  1s   /su  𝑛 )  ·s   1s  ) ) | 
						
							| 43 | 42 | oveq2d | ⊢ ( 𝑞  =   1s   →  ( 𝐵 𝐹 ( (  1s   /su  𝑛 )  ·s  (  1s   /su  𝑞 ) ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑛 )  ·s   1s  ) ) ) | 
						
							| 44 | 43 | eqeq2d | ⊢ ( 𝑞  =   1s   →  ( ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑛 )  ·s  (  1s   /su  𝑞 ) ) )  ↔  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑛 )  ·s   1s  ) ) ) ) | 
						
							| 45 | 37 44 | rspc2ev | ⊢ ( ( 𝑛  ∈  ℕs  ∧   1s   ∈  ℕs  ∧  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑛 )  ·s   1s  ) ) )  →  ∃ 𝑝  ∈  ℕs ∃ 𝑞  ∈  ℕs ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) ) ) | 
						
							| 46 | 33 45 | mp3an2 | ⊢ ( ( 𝑛  ∈  ℕs  ∧  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑛 )  ·s   1s  ) ) )  →  ∃ 𝑝  ∈  ℕs ∃ 𝑞  ∈  ℕs ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) ) ) | 
						
							| 47 | 32 46 | mpdan | ⊢ ( 𝑛  ∈  ℕs  →  ∃ 𝑝  ∈  ℕs ∃ 𝑞  ∈  ℕs ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) ) ) | 
						
							| 48 |  | eqeq1 | ⊢ ( 𝐴  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  →  ( 𝐴  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  ↔  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) ) ) ) | 
						
							| 49 | 48 | 2rexbidv | ⊢ ( 𝐴  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  →  ( ∃ 𝑝  ∈  ℕs ∃ 𝑞  ∈  ℕs 𝐴  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  ↔  ∃ 𝑝  ∈  ℕs ∃ 𝑞  ∈  ℕs ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) ) ) ) | 
						
							| 50 | 47 49 | syl5ibrcom | ⊢ ( 𝑛  ∈  ℕs  →  ( 𝐴  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  →  ∃ 𝑝  ∈  ℕs ∃ 𝑞  ∈  ℕs 𝐴  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) ) ) ) | 
						
							| 51 | 50 | rexlimiv | ⊢ ( ∃ 𝑛  ∈  ℕs 𝐴  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) )  →  ∃ 𝑝  ∈  ℕs ∃ 𝑞  ∈  ℕs 𝐴  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) ) ) | 
						
							| 52 | 25 51 | impbii | ⊢ ( ∃ 𝑝  ∈  ℕs ∃ 𝑞  ∈  ℕs 𝐴  =  ( 𝐵 𝐹 ( (  1s   /su  𝑝 )  ·s  (  1s   /su  𝑞 ) ) )  ↔  ∃ 𝑛  ∈  ℕs 𝐴  =  ( 𝐵 𝐹 (  1s   /su  𝑛 ) ) ) |