:: ISOMICHI semantic presentation  Show TPTP formulae Show IDV graph for whole article:: Showing IDV graph ... (Click the Palm Trees again to close it)

registration
let D be non trivial set ;
cluster ADTS D -> non trivial ;
coherence
not ADTS D is trivial
proof end;
end;

registration
cluster non empty strict anti-discrete non trivial TopStruct ;
existence
ex b1 being TopSpace st
( b1 is anti-discrete & not b1 is trivial & not b1 is empty & b1 is strict )
proof end;
end;

theorem Th1: :: ISOMICHI:1  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A, B being Subset of T holds (Int (Cl (Int A))) /\ (Int (Cl (Int B))) = Int (Cl (Int (A /\ B)))
proof end;

theorem Th2: :: ISOMICHI:2  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A, B being Subset of T holds Cl (Int (Cl (A \/ B))) = (Cl (Int (Cl A))) \/ (Cl (Int (Cl B)))
proof end;

definition
let T be TopStruct ;
let A be Subset of T;
attr A is supercondensed means :Def1: :: ISOMICHI:def 1
Int (Cl A) = Int A;
attr A is subcondensed means :Def2: :: ISOMICHI:def 2
Cl (Int A) = Cl A;
end;

:: deftheorem Def1 defines supercondensed ISOMICHI:def 1 :
for T being TopStruct
for A being Subset of T holds
( A is supercondensed iff Int (Cl A) = Int A );

:: deftheorem Def2 defines subcondensed ISOMICHI:def 2 :
for T being TopStruct
for A being Subset of T holds
( A is subcondensed iff Cl (Int A) = Cl A );

theorem Th3: :: ISOMICHI:3  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T st A is closed holds
A is supercondensed
proof end;

theorem Th4: :: ISOMICHI:4  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T st A is open holds
A is subcondensed
proof end;

definition
let T be TopSpace;
let A be Subset of T;
redefine attr A is condensed means :Def3: :: ISOMICHI:def 3
( Cl (Int A) = Cl A & Int (Cl A) = Int A );
compatibility
( A is condensed iff ( Cl (Int A) = Cl A & Int (Cl A) = Int A ) )
proof end;
end;

:: deftheorem Def3 defines condensed ISOMICHI:def 3 :
for T being TopSpace
for A being Subset of T holds
( A is condensed iff ( Cl (Int A) = Cl A & Int (Cl A) = Int A ) );

theorem Th5: :: ISOMICHI:5  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is condensed iff ( A is subcondensed & A is supercondensed ) )
proof end;

registration
let T be TopSpace;
cluster condensed -> supercondensed subcondensed Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is condensed holds
( b1 is subcondensed & b1 is supercondensed )
by Th5;
cluster supercondensed subcondensed -> condensed Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is subcondensed & b1 is supercondensed holds
b1 is condensed
by Th5;
end;

registration
let T be TopSpace;
cluster condensed supercondensed subcondensed Element of K10(the carrier of T);
existence
ex b1 being Subset of T st
( b1 is condensed & b1 is subcondensed & b1 is supercondensed )
proof end;
end;

theorem :: ISOMICHI:6  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T st A is supercondensed holds
A ` is subcondensed
proof end;

theorem :: ISOMICHI:7  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T st A is subcondensed holds
A ` is supercondensed
proof end;

theorem Th8: :: ISOMICHI:8  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is supercondensed iff Int (Cl A) c= A )
proof end;

theorem Th9: :: ISOMICHI:9  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is subcondensed iff A c= Cl (Int A) )
proof end;

registration
let T be TopSpace;
cluster subcondensed -> semi-open Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is subcondensed holds
b1 is semi-open
proof end;
cluster semi-open -> subcondensed Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is semi-open holds
b1 is subcondensed
proof end;
end;

theorem Th10: :: ISOMICHI:10  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is condensed iff ( Int (Cl A) c= A & A c= Cl (Int A) ) )
proof end;

notation
let T be TopStruct ;
let A be Subset of T;
synonym regular_open A for open_condensed A;
end;

notation
let T be TopStruct ;
let A be Subset of T;
synonym regular_closed A for closed_condensed A;
end;

theorem Th11: :: ISOMICHI:11  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace holds
( [#] T is regular_open & [#] T is regular_closed )
proof end;

registration
let T be TopSpace;
cluster [#] T -> regular_closed regular_open ;
coherence
( [#] T is regular_open & [#] T is regular_closed )
by Th11;
end;

theorem Th12: :: ISOMICHI:12  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for X being TopSpace holds
( {} X is regular_open & {} X is regular_closed )
proof end;

registration
let T be TopSpace;
cluster {} T -> regular_closed regular_open ;
coherence
( {} T is regular_open & {} T is regular_closed )
by Th12;
end;

theorem :: ISOMICHI:13  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
canceled;

theorem :: ISOMICHI:14  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace holds Int (Cl ({} T)) = {} T
proof end;

theorem Th15: :: ISOMICHI:15  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T st A is regular_open holds
A ` is regular_closed
proof end;

registration
let T be TopSpace;
cluster regular_closed regular_open Element of K10(the carrier of T);
existence
ex b1 being Subset of T st
( b1 is regular_open & b1 is regular_closed )
proof end;
end;

registration
let T be TopSpace;
let A be regular_open Subset of T;
cluster A ` -> regular_closed ;
coherence
A ` is regular_closed
by Th15;
end;

theorem Th16: :: ISOMICHI:16  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T st A is regular_closed holds
A ` is regular_open
proof end;

registration
let T be TopSpace;
let A be regular_closed Subset of T;
cluster A ` -> regular_open ;
coherence
A ` is regular_open
by Th16;
end;

registration
let T be TopSpace;
cluster regular_open -> open Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is regular_open holds
b1 is open
by TOPS_1:107;
cluster regular_closed -> closed Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is regular_closed holds
b1 is closed
by TOPS_1:106;
end;

theorem Th17: :: ISOMICHI:17  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( Int (Cl A) is regular_open & Cl (Int A) is regular_closed )
proof end;

registration
let T be TopSpace;
let A be Subset of T;
cluster Int (Cl A) -> regular_open ;
coherence
Int (Cl A) is regular_open
by Th17;
cluster Cl (Int A) -> regular_closed ;
coherence
Cl (Int A) is regular_closed
by Th17;
end;

theorem :: ISOMICHI:18  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is regular_open iff ( A is supercondensed & A is open ) )
proof end;

theorem :: ISOMICHI:19  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is regular_closed iff ( A is subcondensed & A is closed ) )
proof end;

registration
let T be TopSpace;
cluster regular_open -> open condensed semi-open supercondensed subcondensed Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is regular_open holds
( b1 is condensed & b1 is open )
by TOPS_1:107;
cluster open condensed -> open regular_open Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is condensed & b1 is open holds
b1 is regular_open
by TOPS_1:107;
cluster regular_closed -> closed condensed semi-open supercondensed subcondensed Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is regular_closed holds
( b1 is condensed & b1 is closed )
by TOPS_1:106;
cluster closed condensed -> closed regular_closed Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is condensed & b1 is closed holds
b1 is regular_closed
by TOPS_1:106;
end;

theorem :: ISOMICHI:20  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is condensed iff ex B being Subset of T st
( B is regular_open & B c= A & A c= Cl B ) )
proof end;

theorem :: ISOMICHI:21  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is condensed iff ex B being Subset of T st
( B is regular_closed & Int B c= A & A c= B ) )
proof end;

notation
let T be TopStruct ;
let A be Subset of T;
synonym Bound A for Fr A;
end;

definition
let T be TopStruct ;
let A be Subset of T;
redefine func Fr A equals :: ISOMICHI:def 4
(Cl A) \ (Int A);
compatibility
for b1 being Element of K10(the carrier of T) holds
( b1 = Bound A iff b1 = (Cl A) \ (Int A) )
by TOPGEN_1:10;
end;

:: deftheorem defines Bound ISOMICHI:def 4 :
for T being TopStruct
for A being Subset of T holds Bound A = (Cl A) \ (Int A);

theorem Th22: :: ISOMICHI:22  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds Fr A is closed
proof end;

registration
let T be TopSpace;
let A be Subset of T;
cluster Bound A -> closed ;
coherence
Fr A is closed
by Th22;
end;

theorem :: ISOMICHI:23  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is condensed iff ( Fr A = (Cl (Int A)) \ (Int (Cl A)) & Fr A = (Cl (Int A)) /\ (Cl (Int (A ` ))) ) )
proof end;

definition
let T be TopStruct ;
let A be Subset of T;
func Border A -> Subset of T equals :: ISOMICHI:def 5
Int (Fr A);
coherence
Int (Fr A) is Subset of T
;
end;

:: deftheorem defines Border ISOMICHI:def 5 :
for T being TopStruct
for A being Subset of T holds Border A = Int (Fr A);

theorem Th24: :: ISOMICHI:24  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( Border A is regular_open & Border A = (Int (Cl A)) \ (Cl (Int A)) & Border A = (Int (Cl A)) /\ (Int (Cl (A ` ))) )
proof end;

registration
let T be TopSpace;
let A be Subset of T;
cluster Border A -> open condensed regular_open semi-open supercondensed subcondensed ;
coherence
Border A is regular_open
by Th24;
end;

theorem Th25: :: ISOMICHI:25  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is supercondensed iff ( Int A is regular_open & Border A is empty ) )
proof end;

theorem Th26: :: ISOMICHI:26  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is subcondensed iff ( Cl A is regular_closed & Border A is empty ) )
proof end;

registration
let T be TopSpace;
let A be Subset of T;
cluster Border (Border A) -> empty open condensed regular_closed regular_open semi-open supercondensed subcondensed ;
coherence
Border (Border A) is empty
;
end;

theorem :: ISOMICHI:27  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is condensed iff ( Int A is regular_open & Cl A is regular_closed & Border A is empty ) )
proof end;

theorem :: ISOMICHI:28  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for A being Subset of R^1
for a being real number st A = ].-infty, a holds
Int A = ].-infty, a
proof end;

theorem :: ISOMICHI:29  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for A being Subset of R^1
for a being real number st A = [. a holds
Int A = ]. a
proof end;

theorem Th30: :: ISOMICHI:30  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for A being Subset of R^1
for a, b being real number st A = ((].-infty, a) \/ (IRRAT a,b)) \/ ([. b) holds
Cl A = the carrier of R^1
proof end;

theorem :: ISOMICHI:31  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for A being Subset of R^1
for a, b being real number st A = RAT a,b holds
Int A = {}
proof end;

theorem :: ISOMICHI:32  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for A being Subset of R^1
for a, b being real number st A = IRRAT a,b holds
Int A = {}
proof end;

theorem Th33: :: ISOMICHI:33  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for a, b being real number holds (].-infty, a) \ (].-infty, b) = [.b,a.]
proof end;

theorem Th34: :: ISOMICHI:34  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for a, b being real number st a < b holds
[. b misses ].-infty, a
proof end;

theorem Th35: :: ISOMICHI:35  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for a, b being real number st a >= b holds
IRRAT a,b = {}
proof end;

theorem Th36: :: ISOMICHI:36  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for a, b being real number holds IRRAT a,b c= [. a
proof end;

theorem Th37: :: ISOMICHI:37  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for A being Subset of R^1
for a, b, c being real number st A = (].-infty, a) \/ (RAT b,c) & a < b & b < c holds
Int A = ].-infty, a
proof end;

theorem Th38: :: ISOMICHI:38  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for a, b being real number holds [.a,b.] misses ]. b
proof end;

Lm1: for a, b being real number st a < b holds
[.a,b.] \ (]. b) = [.a,b.]
proof end;

Lm2: for a, b being real number st a < b holds
[.a,b.] \/ {b} = [.a,b.]
proof end;

theorem Th39: :: ISOMICHI:39  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for b being real number holds ([. b) \ (]. b) = {b}
proof end;

theorem Th40: :: ISOMICHI:40  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for a, b being real number st a < b holds
[.a,b.] = ([. a) \ (]. b)
proof end;

theorem :: ISOMICHI:41  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for a, b being real number st a < b holds
REAL = ((].-infty, a) \/ [.a,b.]) \/ (]. b)
proof end;

theorem Th42: :: ISOMICHI:42  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for a, b being real number holds ].a,b.[ = (]. a) \ ([. b)
proof end;

theorem Th43: :: ISOMICHI:43  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for a, b, c being real number st b < c & c < a holds
(].-infty, a) \ [.b,c.] = (].-infty, b) \/ ].c,a.[
proof end;

theorem Th44: :: ISOMICHI:44  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for A being Subset of R^1
for a, b, c being real number st A = (].-infty, a) \/ [.b,c.] & a < b & b < c holds
Int A = (].-infty, a) \/ ].b,c.[
proof end;

notation
let A, B be set ;
antonym A,B are_c=-incomparable for A,B are_c=-comparable ;
end;

theorem Th45: :: ISOMICHI:45  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for A, B being set holds
( A,B are_c=-incomparable or A c= B or B c< A )
proof end;

definition
let T be TopSpace;
let A be Subset of T;
attr A is 1st_class means :Def6: :: ISOMICHI:def 6
Int (Cl A) c= Cl (Int A);
attr A is 2nd_class means :Def7: :: ISOMICHI:def 7
Cl (Int A) c< Int (Cl A);
attr A is 3rd_class means :Def8: :: ISOMICHI:def 8
Cl (Int A), Int (Cl A) are_c=-incomparable ;
end;

:: deftheorem Def6 defines 1st_class ISOMICHI:def 6 :
for T being TopSpace
for A being Subset of T holds
( A is 1st_class iff Int (Cl A) c= Cl (Int A) );

:: deftheorem Def7 defines 2nd_class ISOMICHI:def 7 :
for T being TopSpace
for A being Subset of T holds
( A is 2nd_class iff Cl (Int A) c< Int (Cl A) );

:: deftheorem Def8 defines 3rd_class ISOMICHI:def 8 :
for T being TopSpace
for A being Subset of T holds
( A is 3rd_class iff Cl (Int A), Int (Cl A) are_c=-incomparable );

theorem :: ISOMICHI:46  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is 1st_class or A is 2nd_class or A is 3rd_class )
proof end;

registration
let T be TopSpace;
cluster 1st_class -> non 2nd_class non 3rd_class Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is 1st_class holds
( not b1 is 2nd_class & not b1 is 3rd_class )
proof end;
cluster 2nd_class -> non 1st_class non 3rd_class Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is 2nd_class holds
( not b1 is 1st_class & not b1 is 3rd_class )
proof end;
cluster 3rd_class -> non 1st_class non 2nd_class Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is 3rd_class holds
( not b1 is 1st_class & not b1 is 2nd_class )
proof end;
end;

theorem Th47: :: ISOMICHI:47  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is 1st_class iff Border A is empty )
proof end;

registration
let T be TopSpace;
cluster supercondensed -> 1st_class non 2nd_class non 3rd_class Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is supercondensed holds
b1 is 1st_class
proof end;
cluster subcondensed -> 1st_class non 2nd_class non 3rd_class Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is subcondensed holds
b1 is 1st_class
proof end;
end;

definition
let T be TopSpace;
attr T is with_1st_class_subsets means :Def9: :: ISOMICHI:def 9
ex A being Subset of T st A is 1st_class;
attr T is with_2nd_class_subsets means :Def10: :: ISOMICHI:def 10
ex A being Subset of T st A is 2nd_class;
attr T is with_3rd_class_subsets means :Def11: :: ISOMICHI:def 11
ex A being Subset of T st A is 3rd_class;
end;

:: deftheorem Def9 defines with_1st_class_subsets ISOMICHI:def 9 :
for T being TopSpace holds
( T is with_1st_class_subsets iff ex A being Subset of T st A is 1st_class );

:: deftheorem Def10 defines with_2nd_class_subsets ISOMICHI:def 10 :
for T being TopSpace holds
( T is with_2nd_class_subsets iff ex A being Subset of T st A is 2nd_class );

:: deftheorem Def11 defines with_3rd_class_subsets ISOMICHI:def 11 :
for T being TopSpace holds
( T is with_3rd_class_subsets iff ex A being Subset of T st A is 3rd_class );

registration
let T be non empty anti-discrete TopSpace;
cluster non empty proper -> non 1st_class 2nd_class non 3rd_class Element of K10(the carrier of T);
coherence
for b1 being Subset of T st b1 is proper & not b1 is empty holds
b1 is 2nd_class
proof end;
end;

registration
let T be non empty strict anti-discrete non trivial TopSpace;
cluster non 1st_class 2nd_class non 3rd_class Element of K10(the carrier of T);
existence
ex b1 being Subset of T st b1 is 2nd_class
proof end;
end;

registration
cluster non empty strict non trivial with_1st_class_subsets with_2nd_class_subsets TopStruct ;
existence
ex b1 being TopSpace st
( b1 is with_1st_class_subsets & b1 is with_2nd_class_subsets & not b1 is empty & b1 is strict & not b1 is trivial )
proof end;
cluster non empty strict with_3rd_class_subsets TopStruct ;
existence
ex b1 being TopSpace st
( b1 is with_3rd_class_subsets & not b1 is empty & b1 is strict )
proof end;
end;

registration
let T be TopSpace;
cluster 1st_class non 2nd_class non 3rd_class Element of K10(the carrier of T);
existence
ex b1 being Subset of T st b1 is 1st_class
proof end;
end;

registration
let T be with_2nd_class_subsets TopSpace;
cluster non 1st_class 2nd_class non 3rd_class Element of K10(the carrier of T);
existence
ex b1 being Subset of T st b1 is 2nd_class
by Def10;
end;

registration
let T be with_3rd_class_subsets TopSpace;
cluster non 1st_class non 2nd_class 3rd_class Element of K10(the carrier of T);
existence
ex b1 being Subset of T st b1 is 3rd_class
by Def11;
end;

theorem Th48: :: ISOMICHI:48  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is 1st_class iff A ` is 1st_class )
proof end;

theorem Th49: :: ISOMICHI:49  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is 2nd_class iff A ` is 2nd_class )
proof end;

theorem Th50: :: ISOMICHI:50  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T holds
( A is 3rd_class iff A ` is 3rd_class )
proof end;

registration
let T be TopSpace;
let A be 1st_class Subset of T;
cluster A ` -> 1st_class non 2nd_class non 3rd_class ;
coherence
A ` is 1st_class
by Th48;
end;

registration
let T be with_2nd_class_subsets TopSpace;
let A be 2nd_class Subset of T;
cluster A ` -> non 1st_class 2nd_class non 3rd_class ;
coherence
A ` is 2nd_class
by Th49;
end;

registration
let T be with_3rd_class_subsets TopSpace;
let A be 3rd_class Subset of T;
cluster A ` -> non 1st_class non 2nd_class 3rd_class ;
coherence
A ` is 3rd_class
by Th50;
end;

theorem Th51: :: ISOMICHI:51  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T st A is 1st_class holds
( Int (Cl A) = Int (Cl (Int A)) & Cl (Int A) = Cl (Int (Cl A)) )
proof end;

theorem Th52: :: ISOMICHI:52  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A being Subset of T st ( Int (Cl A) = Int (Cl (Int A)) or Cl (Int A) = Cl (Int (Cl A)) ) holds
A is 1st_class
proof end;

theorem Th53: :: ISOMICHI:53  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A, B being Subset of T st A is 1st_class & B is 1st_class holds
( (Int (Cl A)) /\ (Int (Cl B)) = Int (Cl (A /\ B)) & (Cl (Int A)) \/ (Cl (Int B)) = Cl (Int (A \/ B)) )
proof end;

theorem :: ISOMICHI:54  Show TPTP formulae Show IDV graph:: Showing IDV graph ... (Click the Palm Tree again to close it) Show TPTP problem
for T being TopSpace
for A, B being Subset of T st A is 1st_class & B is 1st_class holds
( A \/ B is 1st_class & A /\ B is 1st_class )
proof end;