| Step | Hyp | Ref | Expression | 
						
							| 1 |  | dvdschrmulg.1 |  | 
						
							| 2 |  | dvdschrmulg.2 |  | 
						
							| 3 |  | dvdschrmulg.3 |  | 
						
							| 4 |  | dvdschrmulg.4 |  | 
						
							| 5 |  | simp1 |  | 
						
							| 6 |  | dvdszrcl |  | 
						
							| 7 | 6 | simprd |  | 
						
							| 8 | 7 | 3ad2ant2 |  | 
						
							| 9 |  | eqid |  | 
						
							| 10 | 2 9 | ringidcl |  | 
						
							| 11 | 5 10 | syl |  | 
						
							| 12 |  | simp3 |  | 
						
							| 13 |  | eqid |  | 
						
							| 14 | 2 3 13 | mulgass2 |  | 
						
							| 15 | 5 8 11 12 14 | syl13anc |  | 
						
							| 16 |  | ringgrp |  | 
						
							| 17 | 5 16 | syl |  | 
						
							| 18 |  | eqid |  | 
						
							| 19 | 18 9 1 | chrval |  | 
						
							| 20 |  | simp2 |  | 
						
							| 21 | 19 20 | eqbrtrid |  | 
						
							| 22 | 2 18 3 4 | oddvdsi |  | 
						
							| 23 | 17 11 21 22 | syl3anc |  | 
						
							| 24 | 23 | oveq1d |  | 
						
							| 25 | 2 13 4 | ringlz |  | 
						
							| 26 | 25 | 3adant2 |  | 
						
							| 27 | 24 26 | eqtrd |  | 
						
							| 28 | 2 13 9 | ringlidm |  | 
						
							| 29 | 28 | 3adant2 |  | 
						
							| 30 | 29 | oveq2d |  | 
						
							| 31 | 15 27 30 | 3eqtr3rd |  |