| Step | Hyp | Ref | Expression | 
						
							| 1 |  | 1red | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  1  ∈  ℝ ) | 
						
							| 2 |  | 1nn0 | ⊢ 1  ∈  ℕ0 | 
						
							| 3 | 2 | a1i | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  1  ∈  ℕ0 ) | 
						
							| 4 |  | 0nn0 | ⊢ 0  ∈  ℕ0 | 
						
							| 5 | 4 | a1i | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  0  ∈  ℕ0 ) | 
						
							| 6 |  | eldifi | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  𝐷  ∈  ℕ ) | 
						
							| 7 | 6 | nncnd | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  𝐷  ∈  ℂ ) | 
						
							| 8 | 7 | sqrtcld | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  ( √ ‘ 𝐷 )  ∈  ℂ ) | 
						
							| 9 | 8 | mul01d | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  ( ( √ ‘ 𝐷 )  ·  0 )  =  0 ) | 
						
							| 10 | 9 | oveq2d | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  ( 1  +  ( ( √ ‘ 𝐷 )  ·  0 ) )  =  ( 1  +  0 ) ) | 
						
							| 11 |  | 1p0e1 | ⊢ ( 1  +  0 )  =  1 | 
						
							| 12 | 10 11 | eqtr2di | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  1  =  ( 1  +  ( ( √ ‘ 𝐷 )  ·  0 ) ) ) | 
						
							| 13 |  | sq1 | ⊢ ( 1 ↑ 2 )  =  1 | 
						
							| 14 | 13 | a1i | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  ( 1 ↑ 2 )  =  1 ) | 
						
							| 15 |  | sq0 | ⊢ ( 0 ↑ 2 )  =  0 | 
						
							| 16 | 15 | oveq2i | ⊢ ( 𝐷  ·  ( 0 ↑ 2 ) )  =  ( 𝐷  ·  0 ) | 
						
							| 17 | 7 | mul01d | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  ( 𝐷  ·  0 )  =  0 ) | 
						
							| 18 | 16 17 | eqtrid | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  ( 𝐷  ·  ( 0 ↑ 2 ) )  =  0 ) | 
						
							| 19 | 14 18 | oveq12d | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 0 ↑ 2 ) ) )  =  ( 1  −  0 ) ) | 
						
							| 20 |  | 1m0e1 | ⊢ ( 1  −  0 )  =  1 | 
						
							| 21 | 19 20 | eqtrdi | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 0 ↑ 2 ) ) )  =  1 ) | 
						
							| 22 |  | oveq1 | ⊢ ( 𝑎  =  1  →  ( 𝑎  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) )  =  ( 1  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) ) ) | 
						
							| 23 | 22 | eqeq2d | ⊢ ( 𝑎  =  1  →  ( 1  =  ( 𝑎  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) )  ↔  1  =  ( 1  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) ) ) ) | 
						
							| 24 |  | oveq1 | ⊢ ( 𝑎  =  1  →  ( 𝑎 ↑ 2 )  =  ( 1 ↑ 2 ) ) | 
						
							| 25 | 24 | oveq1d | ⊢ ( 𝑎  =  1  →  ( ( 𝑎 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) )  =  ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) ) ) | 
						
							| 26 | 25 | eqeq1d | ⊢ ( 𝑎  =  1  →  ( ( ( 𝑎 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) )  =  1  ↔  ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) )  =  1 ) ) | 
						
							| 27 | 23 26 | anbi12d | ⊢ ( 𝑎  =  1  →  ( ( 1  =  ( 𝑎  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) )  ∧  ( ( 𝑎 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) )  =  1 )  ↔  ( 1  =  ( 1  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) )  ∧  ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) )  =  1 ) ) ) | 
						
							| 28 |  | oveq2 | ⊢ ( 𝑏  =  0  →  ( ( √ ‘ 𝐷 )  ·  𝑏 )  =  ( ( √ ‘ 𝐷 )  ·  0 ) ) | 
						
							| 29 | 28 | oveq2d | ⊢ ( 𝑏  =  0  →  ( 1  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) )  =  ( 1  +  ( ( √ ‘ 𝐷 )  ·  0 ) ) ) | 
						
							| 30 | 29 | eqeq2d | ⊢ ( 𝑏  =  0  →  ( 1  =  ( 1  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) )  ↔  1  =  ( 1  +  ( ( √ ‘ 𝐷 )  ·  0 ) ) ) ) | 
						
							| 31 |  | oveq1 | ⊢ ( 𝑏  =  0  →  ( 𝑏 ↑ 2 )  =  ( 0 ↑ 2 ) ) | 
						
							| 32 | 31 | oveq2d | ⊢ ( 𝑏  =  0  →  ( 𝐷  ·  ( 𝑏 ↑ 2 ) )  =  ( 𝐷  ·  ( 0 ↑ 2 ) ) ) | 
						
							| 33 | 32 | oveq2d | ⊢ ( 𝑏  =  0  →  ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) )  =  ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 0 ↑ 2 ) ) ) ) | 
						
							| 34 | 33 | eqeq1d | ⊢ ( 𝑏  =  0  →  ( ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) )  =  1  ↔  ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 0 ↑ 2 ) ) )  =  1 ) ) | 
						
							| 35 | 30 34 | anbi12d | ⊢ ( 𝑏  =  0  →  ( ( 1  =  ( 1  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) )  ∧  ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) )  =  1 )  ↔  ( 1  =  ( 1  +  ( ( √ ‘ 𝐷 )  ·  0 ) )  ∧  ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 0 ↑ 2 ) ) )  =  1 ) ) ) | 
						
							| 36 | 27 35 | rspc2ev | ⊢ ( ( 1  ∈  ℕ0  ∧  0  ∈  ℕ0  ∧  ( 1  =  ( 1  +  ( ( √ ‘ 𝐷 )  ·  0 ) )  ∧  ( ( 1 ↑ 2 )  −  ( 𝐷  ·  ( 0 ↑ 2 ) ) )  =  1 ) )  →  ∃ 𝑎  ∈  ℕ0 ∃ 𝑏  ∈  ℕ0 ( 1  =  ( 𝑎  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) )  ∧  ( ( 𝑎 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) )  =  1 ) ) | 
						
							| 37 | 3 5 12 21 36 | syl112anc | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  ∃ 𝑎  ∈  ℕ0 ∃ 𝑏  ∈  ℕ0 ( 1  =  ( 𝑎  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) )  ∧  ( ( 𝑎 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) )  =  1 ) ) | 
						
							| 38 |  | elpell1qr | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  ( 1  ∈  ( Pell1QR ‘ 𝐷 )  ↔  ( 1  ∈  ℝ  ∧  ∃ 𝑎  ∈  ℕ0 ∃ 𝑏  ∈  ℕ0 ( 1  =  ( 𝑎  +  ( ( √ ‘ 𝐷 )  ·  𝑏 ) )  ∧  ( ( 𝑎 ↑ 2 )  −  ( 𝐷  ·  ( 𝑏 ↑ 2 ) ) )  =  1 ) ) ) ) | 
						
							| 39 | 1 37 38 | mpbir2and | ⊢ ( 𝐷  ∈  ( ℕ  ∖  ◻NN )  →  1  ∈  ( Pell1QR ‘ 𝐷 ) ) |