| Step | Hyp | Ref | Expression | 
						
							| 1 |  | gsmsymgrfix.s |  | 
						
							| 2 |  | gsmsymgrfix.b |  | 
						
							| 3 |  | lencl |  | 
						
							| 4 |  | elnn0uz |  | 
						
							| 5 | 3 4 | sylib |  | 
						
							| 6 | 5 | adantr |  | 
						
							| 7 | 6 | 3ad2ant1 |  | 
						
							| 8 |  | fzosplitsn |  | 
						
							| 9 | 7 8 | syl |  | 
						
							| 10 | 9 | raleqdv |  | 
						
							| 11 | 3 | adantr |  | 
						
							| 12 | 11 | 3ad2ant1 |  | 
						
							| 13 |  | fveq2 |  | 
						
							| 14 | 13 | fveq1d |  | 
						
							| 15 | 14 | eqeq1d |  | 
						
							| 16 | 15 | ralunsn |  | 
						
							| 17 | 12 16 | syl |  | 
						
							| 18 | 10 17 | bitrd |  | 
						
							| 19 |  | eqidd |  | 
						
							| 20 |  | ccats1val2 |  | 
						
							| 21 | 20 | fveq1d |  | 
						
							| 22 | 21 | eqeq1d |  | 
						
							| 23 | 19 22 | mpd3an3 |  | 
						
							| 24 | 23 | 3ad2ant1 |  | 
						
							| 25 |  | simprl |  | 
						
							| 26 |  | simpll |  | 
						
							| 27 |  | simplr |  | 
						
							| 28 | 1 2 | gsumccatsymgsn |  | 
						
							| 29 | 28 | fveq1d |  | 
						
							| 30 | 25 26 27 29 | syl3anc |  | 
						
							| 31 | 30 | 3adant3 |  | 
						
							| 32 | 31 | adantr |  | 
						
							| 33 | 1 2 | symgbasf |  | 
						
							| 34 | 33 | ffnd |  | 
						
							| 35 | 34 | adantl |  | 
						
							| 36 |  | simpr |  | 
						
							| 37 |  | fvco2 |  | 
						
							| 38 | 35 36 37 | syl2an |  | 
						
							| 39 | 38 | 3adant3 |  | 
						
							| 40 | 39 | adantr |  | 
						
							| 41 |  | fveq2 |  | 
						
							| 42 | 41 | ad2antrl |  | 
						
							| 43 |  | ccats1val1 |  | 
						
							| 44 | 43 | ad4ant14 |  | 
						
							| 45 | 44 | fveq1d |  | 
						
							| 46 | 45 | eqeq1d |  | 
						
							| 47 | 46 | ralbidva |  | 
						
							| 48 | 47 | biimpd |  | 
						
							| 49 | 48 | adantld |  | 
						
							| 50 | 49 | 3adant3 |  | 
						
							| 51 |  | simp3 |  | 
						
							| 52 | 50 51 | syld |  | 
						
							| 53 | 52 | imp |  | 
						
							| 54 | 42 53 | eqtrd |  | 
						
							| 55 | 32 40 54 | 3eqtrd |  | 
						
							| 56 | 55 | exp32 |  | 
						
							| 57 | 24 56 | sylbid |  | 
						
							| 58 | 57 | impcomd |  | 
						
							| 59 | 18 58 | sylbid |  |