| Step | Hyp | Ref | Expression | 
						
							| 1 |  | omopthlem1.1 |  |-  A e. _om | 
						
							| 2 |  | omopthlem1.2 |  |-  C e. _om | 
						
							| 3 |  | peano2 |  |-  ( A e. _om -> suc A e. _om ) | 
						
							| 4 | 1 3 | ax-mp |  |-  suc A e. _om | 
						
							| 5 |  | nnmwordi |  |-  ( ( suc A e. _om /\ C e. _om /\ suc A e. _om ) -> ( suc A C_ C -> ( suc A .o suc A ) C_ ( suc A .o C ) ) ) | 
						
							| 6 | 4 2 4 5 | mp3an |  |-  ( suc A C_ C -> ( suc A .o suc A ) C_ ( suc A .o C ) ) | 
						
							| 7 |  | nnmwordri |  |-  ( ( suc A e. _om /\ C e. _om /\ C e. _om ) -> ( suc A C_ C -> ( suc A .o C ) C_ ( C .o C ) ) ) | 
						
							| 8 | 4 2 2 7 | mp3an |  |-  ( suc A C_ C -> ( suc A .o C ) C_ ( C .o C ) ) | 
						
							| 9 | 6 8 | sstrd |  |-  ( suc A C_ C -> ( suc A .o suc A ) C_ ( C .o C ) ) | 
						
							| 10 | 1 | nnoni |  |-  A e. On | 
						
							| 11 | 2 | nnoni |  |-  C e. On | 
						
							| 12 | 10 11 | onsucssi |  |-  ( A e. C <-> suc A C_ C ) | 
						
							| 13 | 1 1 | nnmcli |  |-  ( A .o A ) e. _om | 
						
							| 14 |  | 2onn |  |-  2o e. _om | 
						
							| 15 | 1 14 | nnmcli |  |-  ( A .o 2o ) e. _om | 
						
							| 16 | 13 15 | nnacli |  |-  ( ( A .o A ) +o ( A .o 2o ) ) e. _om | 
						
							| 17 | 16 | nnoni |  |-  ( ( A .o A ) +o ( A .o 2o ) ) e. On | 
						
							| 18 | 2 2 | nnmcli |  |-  ( C .o C ) e. _om | 
						
							| 19 | 18 | nnoni |  |-  ( C .o C ) e. On | 
						
							| 20 | 17 19 | onsucssi |  |-  ( ( ( A .o A ) +o ( A .o 2o ) ) e. ( C .o C ) <-> suc ( ( A .o A ) +o ( A .o 2o ) ) C_ ( C .o C ) ) | 
						
							| 21 | 4 1 | nnmcli |  |-  ( suc A .o A ) e. _om | 
						
							| 22 |  | nnasuc |  |-  ( ( ( suc A .o A ) e. _om /\ A e. _om ) -> ( ( suc A .o A ) +o suc A ) = suc ( ( suc A .o A ) +o A ) ) | 
						
							| 23 | 21 1 22 | mp2an |  |-  ( ( suc A .o A ) +o suc A ) = suc ( ( suc A .o A ) +o A ) | 
						
							| 24 |  | nnmsuc |  |-  ( ( suc A e. _om /\ A e. _om ) -> ( suc A .o suc A ) = ( ( suc A .o A ) +o suc A ) ) | 
						
							| 25 | 4 1 24 | mp2an |  |-  ( suc A .o suc A ) = ( ( suc A .o A ) +o suc A ) | 
						
							| 26 |  | nnaass |  |-  ( ( ( A .o A ) e. _om /\ A e. _om /\ A e. _om ) -> ( ( ( A .o A ) +o A ) +o A ) = ( ( A .o A ) +o ( A +o A ) ) ) | 
						
							| 27 | 13 1 1 26 | mp3an |  |-  ( ( ( A .o A ) +o A ) +o A ) = ( ( A .o A ) +o ( A +o A ) ) | 
						
							| 28 |  | nnmcom |  |-  ( ( suc A e. _om /\ A e. _om ) -> ( suc A .o A ) = ( A .o suc A ) ) | 
						
							| 29 | 4 1 28 | mp2an |  |-  ( suc A .o A ) = ( A .o suc A ) | 
						
							| 30 |  | nnmsuc |  |-  ( ( A e. _om /\ A e. _om ) -> ( A .o suc A ) = ( ( A .o A ) +o A ) ) | 
						
							| 31 | 1 1 30 | mp2an |  |-  ( A .o suc A ) = ( ( A .o A ) +o A ) | 
						
							| 32 | 29 31 | eqtri |  |-  ( suc A .o A ) = ( ( A .o A ) +o A ) | 
						
							| 33 | 32 | oveq1i |  |-  ( ( suc A .o A ) +o A ) = ( ( ( A .o A ) +o A ) +o A ) | 
						
							| 34 |  | nnm2 |  |-  ( A e. _om -> ( A .o 2o ) = ( A +o A ) ) | 
						
							| 35 | 1 34 | ax-mp |  |-  ( A .o 2o ) = ( A +o A ) | 
						
							| 36 | 35 | oveq2i |  |-  ( ( A .o A ) +o ( A .o 2o ) ) = ( ( A .o A ) +o ( A +o A ) ) | 
						
							| 37 | 27 33 36 | 3eqtr4ri |  |-  ( ( A .o A ) +o ( A .o 2o ) ) = ( ( suc A .o A ) +o A ) | 
						
							| 38 |  | suceq |  |-  ( ( ( A .o A ) +o ( A .o 2o ) ) = ( ( suc A .o A ) +o A ) -> suc ( ( A .o A ) +o ( A .o 2o ) ) = suc ( ( suc A .o A ) +o A ) ) | 
						
							| 39 | 37 38 | ax-mp |  |-  suc ( ( A .o A ) +o ( A .o 2o ) ) = suc ( ( suc A .o A ) +o A ) | 
						
							| 40 | 23 25 39 | 3eqtr4ri |  |-  suc ( ( A .o A ) +o ( A .o 2o ) ) = ( suc A .o suc A ) | 
						
							| 41 | 40 | sseq1i |  |-  ( suc ( ( A .o A ) +o ( A .o 2o ) ) C_ ( C .o C ) <-> ( suc A .o suc A ) C_ ( C .o C ) ) | 
						
							| 42 | 20 41 | bitri |  |-  ( ( ( A .o A ) +o ( A .o 2o ) ) e. ( C .o C ) <-> ( suc A .o suc A ) C_ ( C .o C ) ) | 
						
							| 43 | 9 12 42 | 3imtr4i |  |-  ( A e. C -> ( ( A .o A ) +o ( A .o 2o ) ) e. ( C .o C ) ) |