| Step | Hyp | Ref | Expression | 
						
							| 1 |  | odcl.1 |  |-  X = ( Base ` G ) | 
						
							| 2 |  | odcl.2 |  |-  O = ( od ` G ) | 
						
							| 3 |  | odid.3 |  |-  .x. = ( .g ` G ) | 
						
							| 4 |  | odid.4 |  |-  .0. = ( 0g ` G ) | 
						
							| 5 |  | simpl3 |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> N e. ZZ ) | 
						
							| 6 | 5 | zred |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> N e. RR ) | 
						
							| 7 |  | simpr |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( O ` A ) e. NN ) | 
						
							| 8 | 7 | nnrpd |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( O ` A ) e. RR+ ) | 
						
							| 9 |  | modval |  |-  ( ( N e. RR /\ ( O ` A ) e. RR+ ) -> ( N mod ( O ` A ) ) = ( N - ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) ) ) | 
						
							| 10 | 6 8 9 | syl2anc |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( N mod ( O ` A ) ) = ( N - ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) ) ) | 
						
							| 11 | 10 | oveq1d |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( N mod ( O ` A ) ) .x. A ) = ( ( N - ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) ) .x. A ) ) | 
						
							| 12 |  | simpl1 |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> G e. Grp ) | 
						
							| 13 | 7 | nnzd |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( O ` A ) e. ZZ ) | 
						
							| 14 | 6 7 | nndivred |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( N / ( O ` A ) ) e. RR ) | 
						
							| 15 | 14 | flcld |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( |_ ` ( N / ( O ` A ) ) ) e. ZZ ) | 
						
							| 16 | 13 15 | zmulcld |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) e. ZZ ) | 
						
							| 17 |  | simpl2 |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> A e. X ) | 
						
							| 18 |  | eqid |  |-  ( -g ` G ) = ( -g ` G ) | 
						
							| 19 | 1 3 18 | mulgsubdir |  |-  ( ( G e. Grp /\ ( N e. ZZ /\ ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) e. ZZ /\ A e. X ) ) -> ( ( N - ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) ) .x. A ) = ( ( N .x. A ) ( -g ` G ) ( ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) .x. A ) ) ) | 
						
							| 20 | 12 5 16 17 19 | syl13anc |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( N - ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) ) .x. A ) = ( ( N .x. A ) ( -g ` G ) ( ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) .x. A ) ) ) | 
						
							| 21 |  | nncn |  |-  ( ( O ` A ) e. NN -> ( O ` A ) e. CC ) | 
						
							| 22 |  | zcn |  |-  ( ( |_ ` ( N / ( O ` A ) ) ) e. ZZ -> ( |_ ` ( N / ( O ` A ) ) ) e. CC ) | 
						
							| 23 |  | mulcom |  |-  ( ( ( O ` A ) e. CC /\ ( |_ ` ( N / ( O ` A ) ) ) e. CC ) -> ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) = ( ( |_ ` ( N / ( O ` A ) ) ) x. ( O ` A ) ) ) | 
						
							| 24 | 21 22 23 | syl2an |  |-  ( ( ( O ` A ) e. NN /\ ( |_ ` ( N / ( O ` A ) ) ) e. ZZ ) -> ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) = ( ( |_ ` ( N / ( O ` A ) ) ) x. ( O ` A ) ) ) | 
						
							| 25 | 7 15 24 | syl2anc |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) = ( ( |_ ` ( N / ( O ` A ) ) ) x. ( O ` A ) ) ) | 
						
							| 26 | 25 | oveq1d |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) .x. A ) = ( ( ( |_ ` ( N / ( O ` A ) ) ) x. ( O ` A ) ) .x. A ) ) | 
						
							| 27 | 1 3 | mulgass |  |-  ( ( G e. Grp /\ ( ( |_ ` ( N / ( O ` A ) ) ) e. ZZ /\ ( O ` A ) e. ZZ /\ A e. X ) ) -> ( ( ( |_ ` ( N / ( O ` A ) ) ) x. ( O ` A ) ) .x. A ) = ( ( |_ ` ( N / ( O ` A ) ) ) .x. ( ( O ` A ) .x. A ) ) ) | 
						
							| 28 | 12 15 13 17 27 | syl13anc |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( ( |_ ` ( N / ( O ` A ) ) ) x. ( O ` A ) ) .x. A ) = ( ( |_ ` ( N / ( O ` A ) ) ) .x. ( ( O ` A ) .x. A ) ) ) | 
						
							| 29 | 1 2 3 4 | odid |  |-  ( A e. X -> ( ( O ` A ) .x. A ) = .0. ) | 
						
							| 30 | 17 29 | syl |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( O ` A ) .x. A ) = .0. ) | 
						
							| 31 | 30 | oveq2d |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( |_ ` ( N / ( O ` A ) ) ) .x. ( ( O ` A ) .x. A ) ) = ( ( |_ ` ( N / ( O ` A ) ) ) .x. .0. ) ) | 
						
							| 32 | 1 3 4 | mulgz |  |-  ( ( G e. Grp /\ ( |_ ` ( N / ( O ` A ) ) ) e. ZZ ) -> ( ( |_ ` ( N / ( O ` A ) ) ) .x. .0. ) = .0. ) | 
						
							| 33 | 12 15 32 | syl2anc |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( |_ ` ( N / ( O ` A ) ) ) .x. .0. ) = .0. ) | 
						
							| 34 | 31 33 | eqtrd |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( |_ ` ( N / ( O ` A ) ) ) .x. ( ( O ` A ) .x. A ) ) = .0. ) | 
						
							| 35 | 26 28 34 | 3eqtrd |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) .x. A ) = .0. ) | 
						
							| 36 | 35 | oveq2d |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( N .x. A ) ( -g ` G ) ( ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) .x. A ) ) = ( ( N .x. A ) ( -g ` G ) .0. ) ) | 
						
							| 37 | 1 3 | mulgcl |  |-  ( ( G e. Grp /\ N e. ZZ /\ A e. X ) -> ( N .x. A ) e. X ) | 
						
							| 38 | 12 5 17 37 | syl3anc |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( N .x. A ) e. X ) | 
						
							| 39 | 1 4 18 | grpsubid1 |  |-  ( ( G e. Grp /\ ( N .x. A ) e. X ) -> ( ( N .x. A ) ( -g ` G ) .0. ) = ( N .x. A ) ) | 
						
							| 40 | 12 38 39 | syl2anc |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( N .x. A ) ( -g ` G ) .0. ) = ( N .x. A ) ) | 
						
							| 41 | 36 40 | eqtrd |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( N .x. A ) ( -g ` G ) ( ( ( O ` A ) x. ( |_ ` ( N / ( O ` A ) ) ) ) .x. A ) ) = ( N .x. A ) ) | 
						
							| 42 | 11 20 41 | 3eqtrd |  |-  ( ( ( G e. Grp /\ A e. X /\ N e. ZZ ) /\ ( O ` A ) e. NN ) -> ( ( N mod ( O ` A ) ) .x. A ) = ( N .x. A ) ) |