| Step | 
						Hyp | 
						Ref | 
						Expression | 
					
						
							| 1 | 
							
								
							 | 
							paddass.a | 
							 |-  A = ( Atoms ` K )  | 
						
						
							| 2 | 
							
								
							 | 
							paddass.p | 
							 |-  .+ = ( +P ` K )  | 
						
						
							| 3 | 
							
								
							 | 
							ianor | 
							 |-  ( -. ( ( X =/= (/) /\ ( Y .+ Z ) =/= (/) ) /\ ( Y =/= (/) /\ Z =/= (/) ) ) <-> ( -. ( X =/= (/) /\ ( Y .+ Z ) =/= (/) ) \/ -. ( Y =/= (/) /\ Z =/= (/) ) ) )  | 
						
						
							| 4 | 
							
								
							 | 
							ianor | 
							 |-  ( -. ( X =/= (/) /\ ( Y .+ Z ) =/= (/) ) <-> ( -. X =/= (/) \/ -. ( Y .+ Z ) =/= (/) ) )  | 
						
						
							| 5 | 
							
								
							 | 
							nne | 
							 |-  ( -. X =/= (/) <-> X = (/) )  | 
						
						
							| 6 | 
							
								
							 | 
							nne | 
							 |-  ( -. ( Y .+ Z ) =/= (/) <-> ( Y .+ Z ) = (/) )  | 
						
						
							| 7 | 
							
								5 6
							 | 
							orbi12i | 
							 |-  ( ( -. X =/= (/) \/ -. ( Y .+ Z ) =/= (/) ) <-> ( X = (/) \/ ( Y .+ Z ) = (/) ) )  | 
						
						
							| 8 | 
							
								4 7
							 | 
							bitri | 
							 |-  ( -. ( X =/= (/) /\ ( Y .+ Z ) =/= (/) ) <-> ( X = (/) \/ ( Y .+ Z ) = (/) ) )  | 
						
						
							| 9 | 
							
								
							 | 
							ianor | 
							 |-  ( -. ( Y =/= (/) /\ Z =/= (/) ) <-> ( -. Y =/= (/) \/ -. Z =/= (/) ) )  | 
						
						
							| 10 | 
							
								
							 | 
							nne | 
							 |-  ( -. Y =/= (/) <-> Y = (/) )  | 
						
						
							| 11 | 
							
								
							 | 
							nne | 
							 |-  ( -. Z =/= (/) <-> Z = (/) )  | 
						
						
							| 12 | 
							
								10 11
							 | 
							orbi12i | 
							 |-  ( ( -. Y =/= (/) \/ -. Z =/= (/) ) <-> ( Y = (/) \/ Z = (/) ) )  | 
						
						
							| 13 | 
							
								9 12
							 | 
							bitri | 
							 |-  ( -. ( Y =/= (/) /\ Z =/= (/) ) <-> ( Y = (/) \/ Z = (/) ) )  | 
						
						
							| 14 | 
							
								8 13
							 | 
							orbi12i | 
							 |-  ( ( -. ( X =/= (/) /\ ( Y .+ Z ) =/= (/) ) \/ -. ( Y =/= (/) /\ Z =/= (/) ) ) <-> ( ( X = (/) \/ ( Y .+ Z ) = (/) ) \/ ( Y = (/) \/ Z = (/) ) ) )  | 
						
						
							| 15 | 
							
								3 14
							 | 
							bitri | 
							 |-  ( -. ( ( X =/= (/) /\ ( Y .+ Z ) =/= (/) ) /\ ( Y =/= (/) /\ Z =/= (/) ) ) <-> ( ( X = (/) \/ ( Y .+ Z ) = (/) ) \/ ( Y = (/) \/ Z = (/) ) ) )  | 
						
						
							| 16 | 
							
								1 2
							 | 
							paddssat | 
							 |-  ( ( K e. HL /\ Y C_ A /\ Z C_ A ) -> ( Y .+ Z ) C_ A )  | 
						
						
							| 17 | 
							
								16
							 | 
							3adant3r1 | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( Y .+ Z ) C_ A )  | 
						
						
							| 18 | 
							
								1 2
							 | 
							padd02 | 
							 |-  ( ( K e. HL /\ ( Y .+ Z ) C_ A ) -> ( (/) .+ ( Y .+ Z ) ) = ( Y .+ Z ) )  | 
						
						
							| 19 | 
							
								17 18
							 | 
							syldan | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( (/) .+ ( Y .+ Z ) ) = ( Y .+ Z ) )  | 
						
						
							| 20 | 
							
								1 2
							 | 
							padd02 | 
							 |-  ( ( K e. HL /\ Y C_ A ) -> ( (/) .+ Y ) = Y )  | 
						
						
							| 21 | 
							
								20
							 | 
							3ad2antr2 | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( (/) .+ Y ) = Y )  | 
						
						
							| 22 | 
							
								21
							 | 
							oveq1d | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( ( (/) .+ Y ) .+ Z ) = ( Y .+ Z ) )  | 
						
						
							| 23 | 
							
								19 22
							 | 
							eqtr4d | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( (/) .+ ( Y .+ Z ) ) = ( ( (/) .+ Y ) .+ Z ) )  | 
						
						
							| 24 | 
							
								
							 | 
							oveq1 | 
							 |-  ( X = (/) -> ( X .+ ( Y .+ Z ) ) = ( (/) .+ ( Y .+ Z ) ) )  | 
						
						
							| 25 | 
							
								
							 | 
							oveq1 | 
							 |-  ( X = (/) -> ( X .+ Y ) = ( (/) .+ Y ) )  | 
						
						
							| 26 | 
							
								25
							 | 
							oveq1d | 
							 |-  ( X = (/) -> ( ( X .+ Y ) .+ Z ) = ( ( (/) .+ Y ) .+ Z ) )  | 
						
						
							| 27 | 
							
								24 26
							 | 
							eqeq12d | 
							 |-  ( X = (/) -> ( ( X .+ ( Y .+ Z ) ) = ( ( X .+ Y ) .+ Z ) <-> ( (/) .+ ( Y .+ Z ) ) = ( ( (/) .+ Y ) .+ Z ) ) )  | 
						
						
							| 28 | 
							
								23 27
							 | 
							syl5ibrcom | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( X = (/) -> ( X .+ ( Y .+ Z ) ) = ( ( X .+ Y ) .+ Z ) ) )  | 
						
						
							| 29 | 
							
								
							 | 
							eqimss | 
							 |-  ( ( X .+ ( Y .+ Z ) ) = ( ( X .+ Y ) .+ Z ) -> ( X .+ ( Y .+ Z ) ) C_ ( ( X .+ Y ) .+ Z ) )  | 
						
						
							| 30 | 
							
								28 29
							 | 
							syl6 | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( X = (/) -> ( X .+ ( Y .+ Z ) ) C_ ( ( X .+ Y ) .+ Z ) ) )  | 
						
						
							| 31 | 
							
								1 2
							 | 
							padd01 | 
							 |-  ( ( K e. HL /\ X C_ A ) -> ( X .+ (/) ) = X )  | 
						
						
							| 32 | 
							
								31
							 | 
							3ad2antr1 | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( X .+ (/) ) = X )  | 
						
						
							| 33 | 
							
								1 2
							 | 
							sspadd1 | 
							 |-  ( ( K e. HL /\ X C_ A /\ Y C_ A ) -> X C_ ( X .+ Y ) )  | 
						
						
							| 34 | 
							
								33
							 | 
							3adant3r3 | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> X C_ ( X .+ Y ) )  | 
						
						
							| 35 | 
							
								
							 | 
							simpl | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> K e. HL )  | 
						
						
							| 36 | 
							
								1 2
							 | 
							paddssat | 
							 |-  ( ( K e. HL /\ X C_ A /\ Y C_ A ) -> ( X .+ Y ) C_ A )  | 
						
						
							| 37 | 
							
								36
							 | 
							3adant3r3 | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( X .+ Y ) C_ A )  | 
						
						
							| 38 | 
							
								
							 | 
							simpr3 | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> Z C_ A )  | 
						
						
							| 39 | 
							
								1 2
							 | 
							sspadd1 | 
							 |-  ( ( K e. HL /\ ( X .+ Y ) C_ A /\ Z C_ A ) -> ( X .+ Y ) C_ ( ( X .+ Y ) .+ Z ) )  | 
						
						
							| 40 | 
							
								35 37 38 39
							 | 
							syl3anc | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( X .+ Y ) C_ ( ( X .+ Y ) .+ Z ) )  | 
						
						
							| 41 | 
							
								34 40
							 | 
							sstrd | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> X C_ ( ( X .+ Y ) .+ Z ) )  | 
						
						
							| 42 | 
							
								32 41
							 | 
							eqsstrd | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( X .+ (/) ) C_ ( ( X .+ Y ) .+ Z ) )  | 
						
						
							| 43 | 
							
								
							 | 
							oveq2 | 
							 |-  ( ( Y .+ Z ) = (/) -> ( X .+ ( Y .+ Z ) ) = ( X .+ (/) ) )  | 
						
						
							| 44 | 
							
								43
							 | 
							sseq1d | 
							 |-  ( ( Y .+ Z ) = (/) -> ( ( X .+ ( Y .+ Z ) ) C_ ( ( X .+ Y ) .+ Z ) <-> ( X .+ (/) ) C_ ( ( X .+ Y ) .+ Z ) ) )  | 
						
						
							| 45 | 
							
								42 44
							 | 
							syl5ibrcom | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( ( Y .+ Z ) = (/) -> ( X .+ ( Y .+ Z ) ) C_ ( ( X .+ Y ) .+ Z ) ) )  | 
						
						
							| 46 | 
							
								30 45
							 | 
							jaod | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( ( X = (/) \/ ( Y .+ Z ) = (/) ) -> ( X .+ ( Y .+ Z ) ) C_ ( ( X .+ Y ) .+ Z ) ) )  | 
						
						
							| 47 | 
							
								1 2
							 | 
							padd02 | 
							 |-  ( ( K e. HL /\ Z C_ A ) -> ( (/) .+ Z ) = Z )  | 
						
						
							| 48 | 
							
								47
							 | 
							3ad2antr3 | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( (/) .+ Z ) = Z )  | 
						
						
							| 49 | 
							
								48
							 | 
							oveq2d | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( X .+ ( (/) .+ Z ) ) = ( X .+ Z ) )  | 
						
						
							| 50 | 
							
								32
							 | 
							oveq1d | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( ( X .+ (/) ) .+ Z ) = ( X .+ Z ) )  | 
						
						
							| 51 | 
							
								49 50
							 | 
							eqtr4d | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( X .+ ( (/) .+ Z ) ) = ( ( X .+ (/) ) .+ Z ) )  | 
						
						
							| 52 | 
							
								
							 | 
							oveq1 | 
							 |-  ( Y = (/) -> ( Y .+ Z ) = ( (/) .+ Z ) )  | 
						
						
							| 53 | 
							
								52
							 | 
							oveq2d | 
							 |-  ( Y = (/) -> ( X .+ ( Y .+ Z ) ) = ( X .+ ( (/) .+ Z ) ) )  | 
						
						
							| 54 | 
							
								
							 | 
							oveq2 | 
							 |-  ( Y = (/) -> ( X .+ Y ) = ( X .+ (/) ) )  | 
						
						
							| 55 | 
							
								54
							 | 
							oveq1d | 
							 |-  ( Y = (/) -> ( ( X .+ Y ) .+ Z ) = ( ( X .+ (/) ) .+ Z ) )  | 
						
						
							| 56 | 
							
								53 55
							 | 
							eqeq12d | 
							 |-  ( Y = (/) -> ( ( X .+ ( Y .+ Z ) ) = ( ( X .+ Y ) .+ Z ) <-> ( X .+ ( (/) .+ Z ) ) = ( ( X .+ (/) ) .+ Z ) ) )  | 
						
						
							| 57 | 
							
								51 56
							 | 
							syl5ibrcom | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( Y = (/) -> ( X .+ ( Y .+ Z ) ) = ( ( X .+ Y ) .+ Z ) ) )  | 
						
						
							| 58 | 
							
								1 2
							 | 
							padd01 | 
							 |-  ( ( K e. HL /\ Y C_ A ) -> ( Y .+ (/) ) = Y )  | 
						
						
							| 59 | 
							
								58
							 | 
							3ad2antr2 | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( Y .+ (/) ) = Y )  | 
						
						
							| 60 | 
							
								59
							 | 
							oveq2d | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( X .+ ( Y .+ (/) ) ) = ( X .+ Y ) )  | 
						
						
							| 61 | 
							
								1 2
							 | 
							padd01 | 
							 |-  ( ( K e. HL /\ ( X .+ Y ) C_ A ) -> ( ( X .+ Y ) .+ (/) ) = ( X .+ Y ) )  | 
						
						
							| 62 | 
							
								37 61
							 | 
							syldan | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( ( X .+ Y ) .+ (/) ) = ( X .+ Y ) )  | 
						
						
							| 63 | 
							
								60 62
							 | 
							eqtr4d | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( X .+ ( Y .+ (/) ) ) = ( ( X .+ Y ) .+ (/) ) )  | 
						
						
							| 64 | 
							
								
							 | 
							oveq2 | 
							 |-  ( Z = (/) -> ( Y .+ Z ) = ( Y .+ (/) ) )  | 
						
						
							| 65 | 
							
								64
							 | 
							oveq2d | 
							 |-  ( Z = (/) -> ( X .+ ( Y .+ Z ) ) = ( X .+ ( Y .+ (/) ) ) )  | 
						
						
							| 66 | 
							
								
							 | 
							oveq2 | 
							 |-  ( Z = (/) -> ( ( X .+ Y ) .+ Z ) = ( ( X .+ Y ) .+ (/) ) )  | 
						
						
							| 67 | 
							
								65 66
							 | 
							eqeq12d | 
							 |-  ( Z = (/) -> ( ( X .+ ( Y .+ Z ) ) = ( ( X .+ Y ) .+ Z ) <-> ( X .+ ( Y .+ (/) ) ) = ( ( X .+ Y ) .+ (/) ) ) )  | 
						
						
							| 68 | 
							
								63 67
							 | 
							syl5ibrcom | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( Z = (/) -> ( X .+ ( Y .+ Z ) ) = ( ( X .+ Y ) .+ Z ) ) )  | 
						
						
							| 69 | 
							
								57 68
							 | 
							jaod | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( ( Y = (/) \/ Z = (/) ) -> ( X .+ ( Y .+ Z ) ) = ( ( X .+ Y ) .+ Z ) ) )  | 
						
						
							| 70 | 
							
								69 29
							 | 
							syl6 | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( ( Y = (/) \/ Z = (/) ) -> ( X .+ ( Y .+ Z ) ) C_ ( ( X .+ Y ) .+ Z ) ) )  | 
						
						
							| 71 | 
							
								46 70
							 | 
							jaod | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( ( ( X = (/) \/ ( Y .+ Z ) = (/) ) \/ ( Y = (/) \/ Z = (/) ) ) -> ( X .+ ( Y .+ Z ) ) C_ ( ( X .+ Y ) .+ Z ) ) )  | 
						
						
							| 72 | 
							
								15 71
							 | 
							biimtrid | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) ) -> ( -. ( ( X =/= (/) /\ ( Y .+ Z ) =/= (/) ) /\ ( Y =/= (/) /\ Z =/= (/) ) ) -> ( X .+ ( Y .+ Z ) ) C_ ( ( X .+ Y ) .+ Z ) ) )  | 
						
						
							| 73 | 
							
								72
							 | 
							3impia | 
							 |-  ( ( K e. HL /\ ( X C_ A /\ Y C_ A /\ Z C_ A ) /\ -. ( ( X =/= (/) /\ ( Y .+ Z ) =/= (/) ) /\ ( Y =/= (/) /\ Z =/= (/) ) ) ) -> ( X .+ ( Y .+ Z ) ) C_ ( ( X .+ Y ) .+ Z ) )  |