| Step | Hyp | Ref | Expression | 
						
							| 1 |  | etransclem9.k | ⊢ ( 𝜑  →  𝐾  ∈  ℤ ) | 
						
							| 2 |  | etransclem9.kn0 | ⊢ ( 𝜑  →  𝐾  ≠  0 ) | 
						
							| 3 |  | etransclem9.m | ⊢ ( 𝜑  →  𝑀  ∈  ℤ ) | 
						
							| 4 |  | etransclem9.n | ⊢ ( 𝜑  →  𝑁  ∈  ℤ ) | 
						
							| 5 |  | etransclem9.km | ⊢ ( 𝜑  →  ¬  𝐾  ∥  𝑀 ) | 
						
							| 6 |  | etransclem9.kn | ⊢ ( 𝜑  →  𝐾  ∥  𝑁 ) | 
						
							| 7 |  | dvdsval2 | ⊢ ( ( 𝐾  ∈  ℤ  ∧  𝐾  ≠  0  ∧  𝑀  ∈  ℤ )  →  ( 𝐾  ∥  𝑀  ↔  ( 𝑀  /  𝐾 )  ∈  ℤ ) ) | 
						
							| 8 | 1 2 3 7 | syl3anc | ⊢ ( 𝜑  →  ( 𝐾  ∥  𝑀  ↔  ( 𝑀  /  𝐾 )  ∈  ℤ ) ) | 
						
							| 9 | 5 8 | mtbid | ⊢ ( 𝜑  →  ¬  ( 𝑀  /  𝐾 )  ∈  ℤ ) | 
						
							| 10 |  | df-neg | ⊢ - 𝑁  =  ( 0  −  𝑁 ) | 
						
							| 11 | 10 | a1i | ⊢ ( ( 𝜑  ∧  ( 𝑀  +  𝑁 )  =  0 )  →  - 𝑁  =  ( 0  −  𝑁 ) ) | 
						
							| 12 |  | oveq1 | ⊢ ( ( 𝑀  +  𝑁 )  =  0  →  ( ( 𝑀  +  𝑁 )  −  𝑁 )  =  ( 0  −  𝑁 ) ) | 
						
							| 13 | 12 | eqcomd | ⊢ ( ( 𝑀  +  𝑁 )  =  0  →  ( 0  −  𝑁 )  =  ( ( 𝑀  +  𝑁 )  −  𝑁 ) ) | 
						
							| 14 | 13 | adantl | ⊢ ( ( 𝜑  ∧  ( 𝑀  +  𝑁 )  =  0 )  →  ( 0  −  𝑁 )  =  ( ( 𝑀  +  𝑁 )  −  𝑁 ) ) | 
						
							| 15 | 3 | zcnd | ⊢ ( 𝜑  →  𝑀  ∈  ℂ ) | 
						
							| 16 | 4 | zcnd | ⊢ ( 𝜑  →  𝑁  ∈  ℂ ) | 
						
							| 17 | 15 16 | pncand | ⊢ ( 𝜑  →  ( ( 𝑀  +  𝑁 )  −  𝑁 )  =  𝑀 ) | 
						
							| 18 | 17 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝑀  +  𝑁 )  =  0 )  →  ( ( 𝑀  +  𝑁 )  −  𝑁 )  =  𝑀 ) | 
						
							| 19 | 11 14 18 | 3eqtrrd | ⊢ ( ( 𝜑  ∧  ( 𝑀  +  𝑁 )  =  0 )  →  𝑀  =  - 𝑁 ) | 
						
							| 20 | 19 | oveq1d | ⊢ ( ( 𝜑  ∧  ( 𝑀  +  𝑁 )  =  0 )  →  ( 𝑀  /  𝐾 )  =  ( - 𝑁  /  𝐾 ) ) | 
						
							| 21 |  | dvdsnegb | ⊢ ( ( 𝐾  ∈  ℤ  ∧  𝑁  ∈  ℤ )  →  ( 𝐾  ∥  𝑁  ↔  𝐾  ∥  - 𝑁 ) ) | 
						
							| 22 | 1 4 21 | syl2anc | ⊢ ( 𝜑  →  ( 𝐾  ∥  𝑁  ↔  𝐾  ∥  - 𝑁 ) ) | 
						
							| 23 | 6 22 | mpbid | ⊢ ( 𝜑  →  𝐾  ∥  - 𝑁 ) | 
						
							| 24 | 4 | znegcld | ⊢ ( 𝜑  →  - 𝑁  ∈  ℤ ) | 
						
							| 25 |  | dvdsval2 | ⊢ ( ( 𝐾  ∈  ℤ  ∧  𝐾  ≠  0  ∧  - 𝑁  ∈  ℤ )  →  ( 𝐾  ∥  - 𝑁  ↔  ( - 𝑁  /  𝐾 )  ∈  ℤ ) ) | 
						
							| 26 | 1 2 24 25 | syl3anc | ⊢ ( 𝜑  →  ( 𝐾  ∥  - 𝑁  ↔  ( - 𝑁  /  𝐾 )  ∈  ℤ ) ) | 
						
							| 27 | 23 26 | mpbid | ⊢ ( 𝜑  →  ( - 𝑁  /  𝐾 )  ∈  ℤ ) | 
						
							| 28 | 27 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝑀  +  𝑁 )  =  0 )  →  ( - 𝑁  /  𝐾 )  ∈  ℤ ) | 
						
							| 29 | 20 28 | eqeltrd | ⊢ ( ( 𝜑  ∧  ( 𝑀  +  𝑁 )  =  0 )  →  ( 𝑀  /  𝐾 )  ∈  ℤ ) | 
						
							| 30 | 9 29 | mtand | ⊢ ( 𝜑  →  ¬  ( 𝑀  +  𝑁 )  =  0 ) | 
						
							| 31 | 30 | neqned | ⊢ ( 𝜑  →  ( 𝑀  +  𝑁 )  ≠  0 ) |