| Step | Hyp | Ref | Expression | 
						
							| 1 |  | gsummulc1OLD.b |  | 
						
							| 2 |  | gsummulc1OLD.z |  | 
						
							| 3 |  | gsummulc1OLD.p |  | 
						
							| 4 |  | gsummulc1OLD.t |  | 
						
							| 5 |  | gsummulc1OLD.r |  | 
						
							| 6 |  | gsummulc1OLD.a |  | 
						
							| 7 |  | gsummulc1OLD.y |  | 
						
							| 8 |  | gsummulc1OLD.x |  | 
						
							| 9 |  | gsummulc1OLD.n |  | 
						
							| 10 |  | ringcmn |  | 
						
							| 11 | 5 10 | syl |  | 
						
							| 12 |  | ringmnd |  | 
						
							| 13 | 5 12 | syl |  | 
						
							| 14 | 1 4 | ringrghm |  | 
						
							| 15 | 5 7 14 | syl2anc |  | 
						
							| 16 |  | ghmmhm |  | 
						
							| 17 | 15 16 | syl |  | 
						
							| 18 |  | oveq1 |  | 
						
							| 19 |  | oveq1 |  | 
						
							| 20 | 1 2 11 13 6 17 8 9 18 19 | gsummhm2 |  |