| Step | Hyp | Ref | Expression | 
						
							| 1 |  | dyadmbl.1 |  | 
						
							| 2 | 1 | dyadf |  | 
						
							| 3 |  | ffn |  | 
						
							| 4 |  | ovelrn |  | 
						
							| 5 |  | ovelrn |  | 
						
							| 6 | 4 5 | anbi12d |  | 
						
							| 7 | 2 3 6 | mp2b |  | 
						
							| 8 |  | reeanv |  | 
						
							| 9 | 7 8 | bitr4i |  | 
						
							| 10 |  | reeanv |  | 
						
							| 11 |  | nn0re |  | 
						
							| 12 | 11 | ad2antrl |  | 
						
							| 13 |  | nn0re |  | 
						
							| 14 | 13 | ad2antll |  | 
						
							| 15 | 1 | dyaddisjlem |  | 
						
							| 16 |  | ancom |  | 
						
							| 17 |  | ancom |  | 
						
							| 18 | 16 17 | anbi12i |  | 
						
							| 19 | 1 | dyaddisjlem |  | 
						
							| 20 | 18 19 | sylanb |  | 
						
							| 21 |  | orcom |  | 
						
							| 22 |  | incom |  | 
						
							| 23 | 22 | eqeq1i |  | 
						
							| 24 | 21 23 | orbi12i |  | 
						
							| 25 |  | df-3or |  | 
						
							| 26 |  | df-3or |  | 
						
							| 27 | 24 25 26 | 3bitr4i |  | 
						
							| 28 | 20 27 | sylib |  | 
						
							| 29 | 12 14 15 28 | lecasei |  | 
						
							| 30 |  | simpl |  | 
						
							| 31 | 30 | fveq2d |  | 
						
							| 32 |  | simpr |  | 
						
							| 33 | 32 | fveq2d |  | 
						
							| 34 | 31 33 | sseq12d |  | 
						
							| 35 | 33 31 | sseq12d |  | 
						
							| 36 | 30 | fveq2d |  | 
						
							| 37 | 32 | fveq2d |  | 
						
							| 38 | 36 37 | ineq12d |  | 
						
							| 39 | 38 | eqeq1d |  | 
						
							| 40 | 34 35 39 | 3orbi123d |  | 
						
							| 41 | 29 40 | syl5ibrcom |  | 
						
							| 42 | 41 | rexlimdvva |  | 
						
							| 43 | 10 42 | biimtrrid |  | 
						
							| 44 | 43 | rexlimivv |  | 
						
							| 45 | 9 44 | sylbi |  |