| Step | Hyp | Ref | Expression | 
						
							| 1 |  | elfz2nn0 | ⊢ ( 𝐾  ∈  ( 0 ... 𝑀 )  ↔  ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0  ∧  𝐾  ≤  𝑀 ) ) | 
						
							| 2 |  | simpl1 | ⊢ ( ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0  ∧  𝐾  ≤  𝑀 )  ∧  𝐾  ≠  𝑀 )  →  𝐾  ∈  ℕ0 ) | 
						
							| 3 |  | necom | ⊢ ( 𝐾  ≠  𝑀  ↔  𝑀  ≠  𝐾 ) | 
						
							| 4 |  | nn0re | ⊢ ( 𝐾  ∈  ℕ0  →  𝐾  ∈  ℝ ) | 
						
							| 5 |  | nn0re | ⊢ ( 𝑀  ∈  ℕ0  →  𝑀  ∈  ℝ ) | 
						
							| 6 |  | ltlen | ⊢ ( ( 𝐾  ∈  ℝ  ∧  𝑀  ∈  ℝ )  →  ( 𝐾  <  𝑀  ↔  ( 𝐾  ≤  𝑀  ∧  𝑀  ≠  𝐾 ) ) ) | 
						
							| 7 | 4 5 6 | syl2an | ⊢ ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0 )  →  ( 𝐾  <  𝑀  ↔  ( 𝐾  ≤  𝑀  ∧  𝑀  ≠  𝐾 ) ) ) | 
						
							| 8 | 7 | bicomd | ⊢ ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0 )  →  ( ( 𝐾  ≤  𝑀  ∧  𝑀  ≠  𝐾 )  ↔  𝐾  <  𝑀 ) ) | 
						
							| 9 |  | elnn0z | ⊢ ( 𝐾  ∈  ℕ0  ↔  ( 𝐾  ∈  ℤ  ∧  0  ≤  𝐾 ) ) | 
						
							| 10 |  | 0red | ⊢ ( ( 𝐾  ∈  ℤ  ∧  𝑀  ∈  ℕ0 )  →  0  ∈  ℝ ) | 
						
							| 11 |  | zre | ⊢ ( 𝐾  ∈  ℤ  →  𝐾  ∈  ℝ ) | 
						
							| 12 | 11 | adantr | ⊢ ( ( 𝐾  ∈  ℤ  ∧  𝑀  ∈  ℕ0 )  →  𝐾  ∈  ℝ ) | 
						
							| 13 | 5 | adantl | ⊢ ( ( 𝐾  ∈  ℤ  ∧  𝑀  ∈  ℕ0 )  →  𝑀  ∈  ℝ ) | 
						
							| 14 |  | lelttr | ⊢ ( ( 0  ∈  ℝ  ∧  𝐾  ∈  ℝ  ∧  𝑀  ∈  ℝ )  →  ( ( 0  ≤  𝐾  ∧  𝐾  <  𝑀 )  →  0  <  𝑀 ) ) | 
						
							| 15 | 10 12 13 14 | syl3anc | ⊢ ( ( 𝐾  ∈  ℤ  ∧  𝑀  ∈  ℕ0 )  →  ( ( 0  ≤  𝐾  ∧  𝐾  <  𝑀 )  →  0  <  𝑀 ) ) | 
						
							| 16 |  | nn0z | ⊢ ( 𝑀  ∈  ℕ0  →  𝑀  ∈  ℤ ) | 
						
							| 17 |  | elnnz | ⊢ ( 𝑀  ∈  ℕ  ↔  ( 𝑀  ∈  ℤ  ∧  0  <  𝑀 ) ) | 
						
							| 18 | 17 | simplbi2 | ⊢ ( 𝑀  ∈  ℤ  →  ( 0  <  𝑀  →  𝑀  ∈  ℕ ) ) | 
						
							| 19 | 16 18 | syl | ⊢ ( 𝑀  ∈  ℕ0  →  ( 0  <  𝑀  →  𝑀  ∈  ℕ ) ) | 
						
							| 20 | 19 | adantl | ⊢ ( ( 𝐾  ∈  ℤ  ∧  𝑀  ∈  ℕ0 )  →  ( 0  <  𝑀  →  𝑀  ∈  ℕ ) ) | 
						
							| 21 | 15 20 | syld | ⊢ ( ( 𝐾  ∈  ℤ  ∧  𝑀  ∈  ℕ0 )  →  ( ( 0  ≤  𝐾  ∧  𝐾  <  𝑀 )  →  𝑀  ∈  ℕ ) ) | 
						
							| 22 | 21 | expd | ⊢ ( ( 𝐾  ∈  ℤ  ∧  𝑀  ∈  ℕ0 )  →  ( 0  ≤  𝐾  →  ( 𝐾  <  𝑀  →  𝑀  ∈  ℕ ) ) ) | 
						
							| 23 | 22 | impancom | ⊢ ( ( 𝐾  ∈  ℤ  ∧  0  ≤  𝐾 )  →  ( 𝑀  ∈  ℕ0  →  ( 𝐾  <  𝑀  →  𝑀  ∈  ℕ ) ) ) | 
						
							| 24 | 9 23 | sylbi | ⊢ ( 𝐾  ∈  ℕ0  →  ( 𝑀  ∈  ℕ0  →  ( 𝐾  <  𝑀  →  𝑀  ∈  ℕ ) ) ) | 
						
							| 25 | 24 | imp | ⊢ ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0 )  →  ( 𝐾  <  𝑀  →  𝑀  ∈  ℕ ) ) | 
						
							| 26 | 8 25 | sylbid | ⊢ ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0 )  →  ( ( 𝐾  ≤  𝑀  ∧  𝑀  ≠  𝐾 )  →  𝑀  ∈  ℕ ) ) | 
						
							| 27 | 26 | expd | ⊢ ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0 )  →  ( 𝐾  ≤  𝑀  →  ( 𝑀  ≠  𝐾  →  𝑀  ∈  ℕ ) ) ) | 
						
							| 28 | 3 27 | syl7bi | ⊢ ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0 )  →  ( 𝐾  ≤  𝑀  →  ( 𝐾  ≠  𝑀  →  𝑀  ∈  ℕ ) ) ) | 
						
							| 29 | 28 | 3impia | ⊢ ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0  ∧  𝐾  ≤  𝑀 )  →  ( 𝐾  ≠  𝑀  →  𝑀  ∈  ℕ ) ) | 
						
							| 30 | 29 | imp | ⊢ ( ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0  ∧  𝐾  ≤  𝑀 )  ∧  𝐾  ≠  𝑀 )  →  𝑀  ∈  ℕ ) | 
						
							| 31 | 8 | biimpd | ⊢ ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0 )  →  ( ( 𝐾  ≤  𝑀  ∧  𝑀  ≠  𝐾 )  →  𝐾  <  𝑀 ) ) | 
						
							| 32 | 31 | exp4b | ⊢ ( 𝐾  ∈  ℕ0  →  ( 𝑀  ∈  ℕ0  →  ( 𝐾  ≤  𝑀  →  ( 𝑀  ≠  𝐾  →  𝐾  <  𝑀 ) ) ) ) | 
						
							| 33 | 32 | 3imp | ⊢ ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0  ∧  𝐾  ≤  𝑀 )  →  ( 𝑀  ≠  𝐾  →  𝐾  <  𝑀 ) ) | 
						
							| 34 | 3 33 | biimtrid | ⊢ ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0  ∧  𝐾  ≤  𝑀 )  →  ( 𝐾  ≠  𝑀  →  𝐾  <  𝑀 ) ) | 
						
							| 35 | 34 | imp | ⊢ ( ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0  ∧  𝐾  ≤  𝑀 )  ∧  𝐾  ≠  𝑀 )  →  𝐾  <  𝑀 ) | 
						
							| 36 | 2 30 35 | 3jca | ⊢ ( ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0  ∧  𝐾  ≤  𝑀 )  ∧  𝐾  ≠  𝑀 )  →  ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ  ∧  𝐾  <  𝑀 ) ) | 
						
							| 37 | 36 | ex | ⊢ ( ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ0  ∧  𝐾  ≤  𝑀 )  →  ( 𝐾  ≠  𝑀  →  ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ  ∧  𝐾  <  𝑀 ) ) ) | 
						
							| 38 | 1 37 | sylbi | ⊢ ( 𝐾  ∈  ( 0 ... 𝑀 )  →  ( 𝐾  ≠  𝑀  →  ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ  ∧  𝐾  <  𝑀 ) ) ) | 
						
							| 39 | 38 | impcom | ⊢ ( ( 𝐾  ≠  𝑀  ∧  𝐾  ∈  ( 0 ... 𝑀 ) )  →  ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ  ∧  𝐾  <  𝑀 ) ) | 
						
							| 40 |  | elfzo0 | ⊢ ( 𝐾  ∈  ( 0 ..^ 𝑀 )  ↔  ( 𝐾  ∈  ℕ0  ∧  𝑀  ∈  ℕ  ∧  𝐾  <  𝑀 ) ) | 
						
							| 41 | 39 40 | sylibr | ⊢ ( ( 𝐾  ≠  𝑀  ∧  𝐾  ∈  ( 0 ... 𝑀 ) )  →  𝐾  ∈  ( 0 ..^ 𝑀 ) ) |