:: MCART_3 semantic presentation

theorem Th1: :: MCART_3:1
for b1 being set holds
not ( b1 <> {} & ( for b2 being set holds
not ( b2 in b1 & ( for b3, b4, b5, b6, b7, b8, b9, b10 being set holds
( b3 in b4 & b4 in b5 & b5 in b6 & b6 in b7 & b7 in b8 & b8 in b9 & b9 in b10 & b10 in b2 implies b3 misses b1 ) ) ) ) )
proof end;

theorem Th2: :: MCART_3:2
for b1 being set holds
not ( b1 <> {} & ( for b2 being set holds
not ( b2 in b1 & ( for b3, b4, b5, b6, b7, b8, b9, b10, b11 being set holds
( b3 in b4 & b4 in b5 & b5 in b6 & b6 in b7 & b7 in b8 & b8 in b9 & b9 in b10 & b10 in b11 & b11 in b2 implies b3 misses b1 ) ) ) ) )
proof end;

definition
let c1, c2, c3, c4, c5, c6 be set ;
func [c1,c2,c3,c4,c5,c6] -> set equals :: MCART_3:def 1
[[a1,a2,a3,a4,a5],a6];
correctness
coherence
[[c1,c2,c3,c4,c5],c6] is set
;
;
end;

:: deftheorem Def1 defines [ MCART_3:def 1 :
for b1, b2, b3, b4, b5, b6 being set holds [b1,b2,b3,b4,b5,b6] = [[b1,b2,b3,b4,b5],b6];

theorem Th3: :: MCART_3:3
for b1, b2, b3, b4, b5, b6 being set holds [b1,b2,b3,b4,b5,b6] = [[[[[b1,b2],b3],b4],b5],b6]
proof end;

theorem Th4: :: MCART_3:4
canceled;

theorem Th5: :: MCART_3:5
for b1, b2, b3, b4, b5, b6 being set holds [b1,b2,b3,b4,b5,b6] = [[b1,b2,b3,b4],b5,b6]
proof end;

theorem Th6: :: MCART_3:6
for b1, b2, b3, b4, b5, b6 being set holds [b1,b2,b3,b4,b5,b6] = [[b1,b2,b3],b4,b5,b6]
proof end;

theorem Th7: :: MCART_3:7
for b1, b2, b3, b4, b5, b6 being set holds [b1,b2,b3,b4,b5,b6] = [[b1,b2],b3,b4,b5,b6]
proof end;

theorem Th8: :: MCART_3:8
for b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12 being set holds
( [b1,b2,b3,b4,b5,b6] = [b7,b8,b9,b10,b11,b12] implies ( b1 = b7 & b2 = b8 & b3 = b9 & b4 = b10 & b5 = b11 & b6 = b12 ) )
proof end;

theorem Th9: :: MCART_3:9
for b1 being set holds
not ( b1 <> {} & ( for b2 being set holds
not ( b2 in b1 & ( for b3, b4, b5, b6, b7, b8 being set holds
not ( ( b3 in b1 or b4 in b1 ) & b2 = [b3,b4,b5,b6,b7,b8] ) ) ) ) )
proof end;

definition
let c1, c2, c3, c4, c5, c6 be set ;
func [:c1,c2,c3,c4,c5,c6:] -> set equals :: MCART_3:def 2
[:[:a1,a2,a3,a4,a5:],a6:];
coherence
[:[:c1,c2,c3,c4,c5:],c6:] is set
;
end;

:: deftheorem Def2 defines [: MCART_3:def 2 :
for b1, b2, b3, b4, b5, b6 being set holds [:b1,b2,b3,b4,b5,b6:] = [:[:b1,b2,b3,b4,b5:],b6:];

theorem Th10: :: MCART_3:10
for b1, b2, b3, b4, b5, b6 being set holds [:b1,b2,b3,b4,b5,b6:] = [:[:[:[:[:b1,b2:],b3:],b4:],b5:],b6:]
proof end;

theorem Th11: :: MCART_3:11
canceled;

theorem Th12: :: MCART_3:12
for b1, b2, b3, b4, b5, b6 being set holds [:b1,b2,b3,b4,b5,b6:] = [:[:b1,b2,b3,b4:],b5,b6:]
proof end;

theorem Th13: :: MCART_3:13
for b1, b2, b3, b4, b5, b6 being set holds [:b1,b2,b3,b4,b5,b6:] = [:[:b1,b2,b3:],b4,b5,b6:]
proof end;

theorem Th14: :: MCART_3:14
for b1, b2, b3, b4, b5, b6 being set holds [:b1,b2,b3,b4,b5,b6:] = [:[:b1,b2:],b3,b4,b5,b6:]
proof end;

theorem Th15: :: MCART_3:15
for b1, b2, b3, b4, b5, b6 being set holds
( ( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} ) iff [:b1,b2,b3,b4,b5,b6:] <> {} )
proof end;

theorem Th16: :: MCART_3:16
for b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} & [:b1,b2,b3,b4,b5,b6:] = [:b7,b8,b9,b10,b11,b12:] implies ( b1 = b7 & b2 = b8 & b3 = b9 & b4 = b10 & b5 = b11 & b6 = b12 ) )
proof end;

theorem Th17: :: MCART_3:17
for b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12 being set holds
( [:b1,b2,b3,b4,b5,b6:] <> {} & [:b1,b2,b3,b4,b5,b6:] = [:b7,b8,b9,b10,b11,b12:] implies ( b1 = b7 & b2 = b8 & b3 = b9 & b4 = b10 & b5 = b11 & b6 = b12 ) )
proof end;

theorem Th18: :: MCART_3:18
for b1, b2 being set holds
( [:b1,b1,b1,b1,b1,b1:] = [:b2,b2,b2,b2,b2,b2:] implies b1 = b2 )
proof end;

theorem Th19: :: MCART_3:19
for b1, b2, b3, b4, b5, b6 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} implies for b7 being Element of [:b1,b2,b3,b4,b5,b6:] holds
ex b8 being Element of b1ex b9 being Element of b2ex b10 being Element of b3ex b11 being Element of b4ex b12 being Element of b5ex b13 being Element of b6 st b7 = [b8,b9,b10,b11,b12,b13] )
proof end;

definition
let c1, c2, c3, c4, c5, c6 be set ;
assume E11: ( c1 <> {} & c2 <> {} & c3 <> {} & c4 <> {} & c5 <> {} & c6 <> {} ) ;
let c7 be Element of [:c1,c2,c3,c4,c5,c6:];
func c7 `1 -> Element of a1 means :Def3: :: MCART_3:def 3
for b1, b2, b3, b4, b5, b6 being set holds
( a7 = [b1,b2,b3,b4,b5,b6] implies a8 = b1 );
existence
ex b1 being Element of c1 st
for b2, b3, b4, b5, b6, b7 being set holds
( c7 = [b2,b3,b4,b5,b6,b7] implies b1 = b2 )
proof end;
uniqueness
for b1, b2 being Element of c1 holds
( ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b1 = b3 ) ) & ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b2 = b3 ) ) implies b1 = b2 )
proof end;
func c7 `2 -> Element of a2 means :Def4: :: MCART_3:def 4
for b1, b2, b3, b4, b5, b6 being set holds
( a7 = [b1,b2,b3,b4,b5,b6] implies a8 = b2 );
existence
ex b1 being Element of c2 st
for b2, b3, b4, b5, b6, b7 being set holds
( c7 = [b2,b3,b4,b5,b6,b7] implies b1 = b3 )
proof end;
uniqueness
for b1, b2 being Element of c2 holds
( ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b1 = b4 ) ) & ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b2 = b4 ) ) implies b1 = b2 )
proof end;
func c7 `3 -> Element of a3 means :Def5: :: MCART_3:def 5
for b1, b2, b3, b4, b5, b6 being set holds
( a7 = [b1,b2,b3,b4,b5,b6] implies a8 = b3 );
existence
ex b1 being Element of c3 st
for b2, b3, b4, b5, b6, b7 being set holds
( c7 = [b2,b3,b4,b5,b6,b7] implies b1 = b4 )
proof end;
uniqueness
for b1, b2 being Element of c3 holds
( ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b1 = b5 ) ) & ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b2 = b5 ) ) implies b1 = b2 )
proof end;
func c7 `4 -> Element of a4 means :Def6: :: MCART_3:def 6
for b1, b2, b3, b4, b5, b6 being set holds
( a7 = [b1,b2,b3,b4,b5,b6] implies a8 = b4 );
existence
ex b1 being Element of c4 st
for b2, b3, b4, b5, b6, b7 being set holds
( c7 = [b2,b3,b4,b5,b6,b7] implies b1 = b5 )
proof end;
uniqueness
for b1, b2 being Element of c4 holds
( ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b1 = b6 ) ) & ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b2 = b6 ) ) implies b1 = b2 )
proof end;
func c7 `5 -> Element of a5 means :Def7: :: MCART_3:def 7
for b1, b2, b3, b4, b5, b6 being set holds
( a7 = [b1,b2,b3,b4,b5,b6] implies a8 = b5 );
existence
ex b1 being Element of c5 st
for b2, b3, b4, b5, b6, b7 being set holds
( c7 = [b2,b3,b4,b5,b6,b7] implies b1 = b6 )
proof end;
uniqueness
for b1, b2 being Element of c5 holds
( ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b1 = b7 ) ) & ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b2 = b7 ) ) implies b1 = b2 )
proof end;
func c7 `6 -> Element of a6 means :Def8: :: MCART_3:def 8
for b1, b2, b3, b4, b5, b6 being set holds
( a7 = [b1,b2,b3,b4,b5,b6] implies a8 = b6 );
existence
ex b1 being Element of c6 st
for b2, b3, b4, b5, b6, b7 being set holds
( c7 = [b2,b3,b4,b5,b6,b7] implies b1 = b7 )
proof end;
uniqueness
for b1, b2 being Element of c6 holds
( ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b1 = b8 ) ) & ( for b3, b4, b5, b6, b7, b8 being set holds
( c7 = [b3,b4,b5,b6,b7,b8] implies b2 = b8 ) ) implies b1 = b2 )
proof end;
end;

:: deftheorem Def3 defines `1 MCART_3:def 3 :
for b1, b2, b3, b4, b5, b6 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} implies for b7 being Element of [:b1,b2,b3,b4,b5,b6:]
for b8 being Element of b1 holds
( b8 = b7 `1 iff for b9, b10, b11, b12, b13, b14 being set holds
( b7 = [b9,b10,b11,b12,b13,b14] implies b8 = b9 ) ) );

:: deftheorem Def4 defines `2 MCART_3:def 4 :
for b1, b2, b3, b4, b5, b6 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} implies for b7 being Element of [:b1,b2,b3,b4,b5,b6:]
for b8 being Element of b2 holds
( b8 = b7 `2 iff for b9, b10, b11, b12, b13, b14 being set holds
( b7 = [b9,b10,b11,b12,b13,b14] implies b8 = b10 ) ) );

:: deftheorem Def5 defines `3 MCART_3:def 5 :
for b1, b2, b3, b4, b5, b6 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} implies for b7 being Element of [:b1,b2,b3,b4,b5,b6:]
for b8 being Element of b3 holds
( b8 = b7 `3 iff for b9, b10, b11, b12, b13, b14 being set holds
( b7 = [b9,b10,b11,b12,b13,b14] implies b8 = b11 ) ) );

:: deftheorem Def6 defines `4 MCART_3:def 6 :
for b1, b2, b3, b4, b5, b6 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} implies for b7 being Element of [:b1,b2,b3,b4,b5,b6:]
for b8 being Element of b4 holds
( b8 = b7 `4 iff for b9, b10, b11, b12, b13, b14 being set holds
( b7 = [b9,b10,b11,b12,b13,b14] implies b8 = b12 ) ) );

:: deftheorem Def7 defines `5 MCART_3:def 7 :
for b1, b2, b3, b4, b5, b6 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} implies for b7 being Element of [:b1,b2,b3,b4,b5,b6:]
for b8 being Element of b5 holds
( b8 = b7 `5 iff for b9, b10, b11, b12, b13, b14 being set holds
( b7 = [b9,b10,b11,b12,b13,b14] implies b8 = b13 ) ) );

:: deftheorem Def8 defines `6 MCART_3:def 8 :
for b1, b2, b3, b4, b5, b6 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} implies for b7 being Element of [:b1,b2,b3,b4,b5,b6:]
for b8 being Element of b6 holds
( b8 = b7 `6 iff for b9, b10, b11, b12, b13, b14 being set holds
( b7 = [b9,b10,b11,b12,b13,b14] implies b8 = b14 ) ) );

theorem Th20: :: MCART_3:20
for b1, b2, b3, b4, b5, b6 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} implies for b7 being Element of [:b1,b2,b3,b4,b5,b6:]
for b8, b9, b10, b11, b12, b13 being set holds
( b7 = [b8,b9,b10,b11,b12,b13] implies ( b7 `1 = b8 & b7 `2 = b9 & b7 `3 = b10 & b7 `4 = b11 & b7 `5 = b12 & b7 `6 = b13 ) ) ) by Def3, Def4, Def5, Def6, Def7, Def8;

theorem Th21: :: MCART_3:21
for b1, b2, b3, b4, b5, b6 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} implies for b7 being Element of [:b1,b2,b3,b4,b5,b6:] holds b7 = [(b7 `1 ),(b7 `2 ),(b7 `3 ),(b7 `4 ),(b7 `5 ),(b7 `6 )] )
proof end;

theorem Th22: :: MCART_3:22
for b1, b2, b3, b4, b5, b6 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} implies for b7 being Element of [:b1,b2,b3,b4,b5,b6:] holds
( b7 `1 = ((((b7 `1 ) `1 ) `1 ) `1 ) `1 & b7 `2 = ((((b7 `1 ) `1 ) `1 ) `1 ) `2 & b7 `3 = (((b7 `1 ) `1 ) `1 ) `2 & b7 `4 = ((b7 `1 ) `1 ) `2 & b7 `5 = (b7 `1 ) `2 & b7 `6 = b7 `2 ) )
proof end;

theorem Th23: :: MCART_3:23
for b1, b2, b3, b4, b5, b6 being set holds
( not ( not b1 c= [:b1,b2,b3,b4,b5,b6:] & not b1 c= [:b2,b3,b4,b5,b6,b1:] & not b1 c= [:b3,b4,b5,b6,b1,b2:] & not b1 c= [:b4,b5,b6,b1,b2,b3:] & not b1 c= [:b5,b6,b1,b2,b3,b4:] & not b1 c= [:b6,b1,b2,b3,b4,b5:] ) implies b1 = {} )
proof end;

theorem Th24: :: MCART_3:24
for b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12 being set holds
( [:b1,b2,b3,b4,b5,b6:] meets [:b7,b8,b9,b10,b11,b12:] implies ( b1 meets b7 & b2 meets b8 & b3 meets b9 & b4 meets b10 & b5 meets b11 & b6 meets b12 ) )
proof end;

theorem Th25: :: MCART_3:25
for b1, b2, b3, b4, b5, b6 being set holds [:{b1},{b2},{b3},{b4},{b5},{b6}:] = {[b1,b2,b3,b4,b5,b6]}
proof end;

theorem Th26: :: MCART_3:26
for b1, b2, b3, b4, b5, b6 being set
for b7 being Element of [:b1,b2,b3,b4,b5,b6:] holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} implies for b8, b9, b10, b11, b12, b13 being set holds
( b7 = [b8,b9,b10,b11,b12,b13] implies ( b7 `1 = b8 & b7 `2 = b9 & b7 `3 = b10 & b7 `4 = b11 & b7 `5 = b12 & b7 `6 = b13 ) ) ) by Def3, Def4, Def5, Def6, Def7, Def8;

theorem Th27: :: MCART_3:27
for b1, b2, b3, b4, b5, b6, b7 being set
for b8 being Element of [:b1,b2,b3,b4,b5,b6:] holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} & ( for b9 being Element of b1
for b10 being Element of b2
for b11 being Element of b3
for b12 being Element of b4
for b13 being Element of b5
for b14 being Element of b6 holds
( b8 = [b9,b10,b11,b12,b13,b14] implies b7 = b9 ) ) implies b7 = b8 `1 )
proof end;

theorem Th28: :: MCART_3:28
for b1, b2, b3, b4, b5, b6, b7 being set
for b8 being Element of [:b1,b2,b3,b4,b5,b6:] holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} & ( for b9 being Element of b1
for b10 being Element of b2
for b11 being Element of b3
for b12 being Element of b4
for b13 being Element of b5
for b14 being Element of b6 holds
( b8 = [b9,b10,b11,b12,b13,b14] implies b7 = b10 ) ) implies b7 = b8 `2 )
proof end;

theorem Th29: :: MCART_3:29
for b1, b2, b3, b4, b5, b6, b7 being set
for b8 being Element of [:b1,b2,b3,b4,b5,b6:] holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} & ( for b9 being Element of b1
for b10 being Element of b2
for b11 being Element of b3
for b12 being Element of b4
for b13 being Element of b5
for b14 being Element of b6 holds
( b8 = [b9,b10,b11,b12,b13,b14] implies b7 = b11 ) ) implies b7 = b8 `3 )
proof end;

theorem Th30: :: MCART_3:30
for b1, b2, b3, b4, b5, b6, b7 being set
for b8 being Element of [:b1,b2,b3,b4,b5,b6:] holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} & ( for b9 being Element of b1
for b10 being Element of b2
for b11 being Element of b3
for b12 being Element of b4
for b13 being Element of b5
for b14 being Element of b6 holds
( b8 = [b9,b10,b11,b12,b13,b14] implies b7 = b12 ) ) implies b7 = b8 `4 )
proof end;

theorem Th31: :: MCART_3:31
for b1, b2, b3, b4, b5, b6, b7 being set
for b8 being Element of [:b1,b2,b3,b4,b5,b6:] holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} & ( for b9 being Element of b1
for b10 being Element of b2
for b11 being Element of b3
for b12 being Element of b4
for b13 being Element of b5
for b14 being Element of b6 holds
( b8 = [b9,b10,b11,b12,b13,b14] implies b7 = b13 ) ) implies b7 = b8 `5 )
proof end;

theorem Th32: :: MCART_3:32
for b1, b2, b3, b4, b5, b6, b7 being set
for b8 being Element of [:b1,b2,b3,b4,b5,b6:] holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} & ( for b9 being Element of b1
for b10 being Element of b2
for b11 being Element of b3
for b12 being Element of b4
for b13 being Element of b5
for b14 being Element of b6 holds
( b8 = [b9,b10,b11,b12,b13,b14] implies b7 = b14 ) ) implies b7 = b8 `6 )
proof end;

theorem Th33: :: MCART_3:33
for b1, b2, b3, b4, b5, b6, b7 being set holds
not ( b1 in [:b2,b3,b4,b5,b6,b7:] & ( for b8, b9, b10, b11, b12, b13 being set holds
not ( b8 in b2 & b9 in b3 & b10 in b4 & b11 in b5 & b12 in b6 & b13 in b7 & b1 = [b8,b9,b10,b11,b12,b13] ) ) )
proof end;

theorem Th34: :: MCART_3:34
for b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12 being set holds
( [b1,b2,b3,b4,b5,b6] in [:b7,b8,b9,b10,b11,b12:] iff ( b1 in b7 & b2 in b8 & b3 in b9 & b4 in b10 & b5 in b11 & b6 in b12 ) )
proof end;

theorem Th35: :: MCART_3:35
for b1, b2, b3, b4, b5, b6, b7 being set holds
( ( for b8 being set holds
( b8 in b1 iff ex b9, b10, b11, b12, b13, b14 being set st
( b9 in b2 & b10 in b3 & b11 in b4 & b12 in b5 & b13 in b6 & b14 in b7 & b8 = [b9,b10,b11,b12,b13,b14] ) ) ) implies b1 = [:b2,b3,b4,b5,b6,b7:] )
proof end;

theorem Th36: :: MCART_3:36
for b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12 being set holds
( b1 <> {} & b2 <> {} & b3 <> {} & b4 <> {} & b5 <> {} & b6 <> {} & b7 <> {} & b8 <> {} & b9 <> {} & b10 <> {} & b11 <> {} & b12 <> {} implies for b13 being Element of [:b1,b2,b3,b4,b5,b6:]
for b14 being Element of [:b7,b8,b9,b10,b11,b12:] holds
( b13 = b14 implies ( b13 `1 = b14 `1 & b13 `2 = b14 `2 & b13 `3 = b14 `3 & b13 `4 = b14 `4 & b13 `5 = b14 `5 & b13 `6 = b14 `6 ) ) )
proof end;

theorem Th37: :: MCART_3:37
for b1, b2, b3, b4, b5, b6 being set
for b7 being Subset of b1
for b8 being Subset of b2
for b9 being Subset of b3
for b10 being Subset of b4
for b11 being Subset of b5
for b12 being Subset of b6
for b13 being Element of [:b1,b2,b3,b4,b5,b6:] holds
( b13 in [:b7,b8,b9,b10,b11,b12:] implies ( b13 `1 in b7 & b13 `2 in b8 & b13 `3 in b9 & b13 `4 in b10 & b13 `5 in b11 & b13 `6 in b12 ) )
proof end;

theorem Th38: :: MCART_3:38
for b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12 being set holds
( b1 c= b2 & b3 c= b4 & b5 c= b6 & b7 c= b8 & b9 c= b10 & b11 c= b12 implies [:b1,b3,b5,b7,b9,b11:] c= [:b2,b4,b6,b8,b10,b12:] )
proof end;

theorem Th39: :: MCART_3:39
for b1, b2, b3, b4, b5, b6 being set
for b7 being Subset of b1
for b8 being Subset of b2
for b9 being Subset of b3
for b10 being Subset of b4
for b11 being Subset of b5
for b12 being Subset of b6 holds
[:b7,b8,b9,b10,b11,b12:] is Subset of [:b1,b2,b3,b4,b5,b6:] by Th38;