let T be non empty TopSpace; :: thesis: for A being Subset of T holds Kurat14Set A = ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)}
let A be Subset of T; :: thesis: Kurat14Set A = ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)}
set Y1 = {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))};
set Y2 = {A,(A `)};
set Y3 = {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)};
set Y = ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)};
A1: {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} c= ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by XBOOLE_1:7;
A2: ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} c= Kurat14Set A
proof
let x be object ; :: according to TARSKI:def 3 :: thesis: ( not x in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} or x in Kurat14Set A )
assume x in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} ; :: thesis: x in Kurat14Set A
then A3: ( x in {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)} or x in {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} ) by XBOOLE_0:def 3;
per cases ( x in {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} or x in {A,(A `)} or x in {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} ) by A3, XBOOLE_0:def 3;
suppose x in {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} ; :: thesis: x in Kurat14Set A
then ( x = Cl A or x = Cl ((Cl A) `) or x = Cl ((Cl ((Cl A) `)) `) or x = Cl (A `) or x = Cl ((Cl (A `)) `) or x = Cl ((Cl ((Cl (A `)) `)) `) ) by ENUMSET1:def 4;
hence x in Kurat14Set A by Th3, Th4; :: thesis: verum
end;
suppose x in {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} ; :: thesis: x in Kurat14Set A
then ( x = (Cl A) ` or x = (Cl ((Cl A) `)) ` or x = (Cl ((Cl ((Cl A) `)) `)) ` or x = (Cl (A `)) ` or x = (Cl ((Cl (A `)) `)) ` or x = (Cl ((Cl ((Cl (A `)) `)) `)) ` ) by ENUMSET1:def 4;
hence x in Kurat14Set A by Th3, Th4; :: thesis: verum
end;
end;
end;
A4: {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)} c= ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by XBOOLE_1:7;
(Cl ((Cl A) `)) ` in {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by ENUMSET1:def 4;
then A5: (Cl ((Cl A) `)) ` in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A1;
(Cl A) ` in {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by ENUMSET1:def 4;
then A6: (Cl A) ` in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A1;
{A,(A `)} c= {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)} by XBOOLE_1:7;
then A7: {A,(A `)} c= ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A4;
(Cl ((Cl ((Cl (A `)) `)) `)) ` in {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by ENUMSET1:def 4;
then A8: (Cl ((Cl ((Cl (A `)) `)) `)) ` in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A1;
(Cl ((Cl (A `)) `)) ` in {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by ENUMSET1:def 4;
then A9: (Cl ((Cl (A `)) `)) ` in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A1;
(Cl (A `)) ` in {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by ENUMSET1:def 4;
then A10: (Cl (A `)) ` in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A1;
(Cl ((Cl ((Cl A) `)) `)) ` in {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by ENUMSET1:def 4;
then A11: (Cl ((Cl ((Cl A) `)) `)) ` in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A1;
A in {A,(A `)} by TARSKI:def 2;
then A12: A in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A7;
{(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} c= {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)} by XBOOLE_1:7;
then A13: {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} c= ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A4;
A ` in {A,(A `)} by TARSKI:def 2;
then A14: A ` in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A7;
Cl ((Cl ((Cl (A `)) `)) `) in {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} by ENUMSET1:def 4;
then A15: Cl ((Cl ((Cl (A `)) `)) `) in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A13;
Cl ((Cl (A `)) `) in {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} by ENUMSET1:def 4;
then A16: Cl ((Cl (A `)) `) in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A13;
Cl (A `) in {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} by ENUMSET1:def 4;
then A17: Cl (A `) in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A13;
Cl ((Cl ((Cl A) `)) `) in {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} by ENUMSET1:def 4;
then A18: Cl ((Cl ((Cl A) `)) `) in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A13;
Cl ((Cl A) `) in {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} by ENUMSET1:def 4;
then A19: Cl ((Cl A) `) in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A13;
Cl A in {(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} by ENUMSET1:def 4;
then A20: Cl A in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A13;
Kurat14Set A c= ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)}
proof
let x be object ; :: according to TARSKI:def 3 :: thesis: ( not x in Kurat14Set A or x in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} )
assume A21: x in Kurat14Set A ; :: thesis: x in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)}
per cases ( x in {A,(Cl A),((Cl A) `),(Cl ((Cl A) `)),((Cl ((Cl A) `)) `),(Cl ((Cl ((Cl A) `)) `)),((Cl ((Cl ((Cl A) `)) `)) `)} or x in {(A `),(Cl (A `)),((Cl (A `)) `),(Cl ((Cl (A `)) `)),((Cl ((Cl (A `)) `)) `),(Cl ((Cl ((Cl (A `)) `)) `)),((Cl ((Cl ((Cl (A `)) `)) `)) `)} ) by A21, XBOOLE_0:def 3;
suppose x in {A,(Cl A),((Cl A) `),(Cl ((Cl A) `)),((Cl ((Cl A) `)) `),(Cl ((Cl ((Cl A) `)) `)),((Cl ((Cl ((Cl A) `)) `)) `)} ; :: thesis: x in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)}
hence x in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A20, A19, A18, A12, A6, A5, A11, ENUMSET1:def 5; :: thesis: verum
end;
suppose x in {(A `),(Cl (A `)),((Cl (A `)) `),(Cl ((Cl (A `)) `)),((Cl ((Cl (A `)) `)) `),(Cl ((Cl ((Cl (A `)) `)) `)),((Cl ((Cl ((Cl (A `)) `)) `)) `)} ; :: thesis: x in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)}
hence x in ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A17, A16, A15, A14, A10, A9, A8, ENUMSET1:def 5; :: thesis: verum
end;
end;
end;
hence Kurat14Set A = ({(Cl A),(Cl ((Cl A) `)),(Cl ((Cl ((Cl A) `)) `)),(Cl (A `)),(Cl ((Cl (A `)) `)),(Cl ((Cl ((Cl (A `)) `)) `))} \/ {A,(A `)}) \/ {((Cl A) `),((Cl ((Cl A) `)) `),((Cl ((Cl ((Cl A) `)) `)) `),((Cl (A `)) `),((Cl ((Cl (A `)) `)) `),((Cl ((Cl ((Cl (A `)) `)) `)) `)} by A2, XBOOLE_0:def 10; :: thesis: verum