let n be Nat; :: thesis: ( not Necklace n, ComplRelStr (Necklace n) are_isomorphic or n = 0 or n = 1 or n = 4 )
assume A1: Necklace n, ComplRelStr (Necklace n) are_isomorphic ; :: thesis: ( n = 0 or n = 1 or n = 4 )
assume A2: ( not n = 0 & not n = 1 & not n = 4 ) ; :: thesis: contradiction
per cases ( n = 2 or n = 3 or n > 4 ) by A2, NAT_1:29;
suppose A3: n = 2 ; :: thesis: contradiction
set S = Necklace 2;
set T = ComplRelStr (Necklace 2);
set X = {[0 ,1],[1,0 ]};
set Y = the InternalRel of (Necklace 2);
A4: card the InternalRel of (Necklace 2) = 2 * (2 - 1) by Th28
.= 2 ;
A5: the InternalRel of (Necklace 2) = { [i,(i + 1)] where i is Element of NAT : i + 1 < 2 } \/ { [(i + 1),i] where i is Element of NAT : i + 1 < 2 } by Th19;
A6: [0 ,(0 + 1)] in { [i,(i + 1)] where i is Element of NAT : i + 1 < 2 } ;
A7: [(0 + 1),0 ] in { [(i + 1),i] where i is Element of NAT : i + 1 < 2 } ;
A8: {[0 ,1],[1,0 ]} c= the InternalRel of (Necklace 2)
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in {[0 ,1],[1,0 ]} or x in the InternalRel of (Necklace 2) )
assume A9: x in {[0 ,1],[1,0 ]} ; :: thesis: x in the InternalRel of (Necklace 2)
end;
A10: the InternalRel of (Necklace 2) c= {[0 ,1],[1,0 ]}
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in the InternalRel of (Necklace 2) or x in {[0 ,1],[1,0 ]} )
assume A11: x in the InternalRel of (Necklace 2) ; :: thesis: x in {[0 ,1],[1,0 ]}
then consider y, z being set such that
A12: x = [y,z] by RELAT_1:def 1;
per cases ( x in { [i,(i + 1)] where i is Element of NAT : i + 1 < 2 } or x in { [(i + 1),i] where i is Element of NAT : i + 1 < 2 } ) by A5, A11, XBOOLE_0:def 3;
suppose x in { [i,(i + 1)] where i is Element of NAT : i + 1 < 2 } ; :: thesis: x in {[0 ,1],[1,0 ]}
then consider i being Element of NAT such that
A13: ( [y,z] = [i,(i + 1)] & i + 1 < 2 ) by A12;
A14: ( y = i & z = i + 1 ) by A13, ZFMISC_1:33;
i + 1 < 1 + 1 by A13;
then i < 0 + 1 by XREAL_1:9;
then i <= 0 by NAT_1:13;
then y = 0 by A14, NAT_1:3;
hence x in {[0 ,1],[1,0 ]} by A12, A14, TARSKI:def 2; :: thesis: verum
end;
suppose x in { [(i + 1),i] where i is Element of NAT : i + 1 < 2 } ; :: thesis: x in {[0 ,1],[1,0 ]}
then consider i being Element of NAT such that
A15: ( [y,z] = [(i + 1),i] & i + 1 < 2 ) by A12;
A16: ( y = i + 1 & z = i ) by A15, ZFMISC_1:33;
i + 1 < 1 + 1 by A15;
then i < 0 + 1 by XREAL_1:9;
then i <= 0 by NAT_1:13;
then z = 0 by A16, NAT_1:3;
hence x in {[0 ,1],[1,0 ]} by A12, A16, TARSKI:def 2; :: thesis: verum
end;
end;
end;
then A17: {[0 ,1],[1,0 ]} = the InternalRel of (Necklace 2) by A8, XBOOLE_0:def 10;
the InternalRel of (ComplRelStr (Necklace 2)) is empty
proof
assume not the InternalRel of (ComplRelStr (Necklace 2)) is empty ; :: thesis: contradiction
then consider x being set such that
A18: x in the InternalRel of (ComplRelStr (Necklace 2)) by XBOOLE_0:def 1;
x in (the InternalRel of (Necklace 2) ` ) \ (id the carrier of (Necklace 2)) by A18, Def9;
then A19: ( x in the InternalRel of (Necklace 2) ` & not x in id the carrier of (Necklace 2) ) by XBOOLE_0:def 5;
A20: the carrier of (Necklace 2) = the carrier of (2 -SuccRelStr ) by Def8
.= {0 ,1} by Def7, CARD_1:88 ;
A21: id the carrier of (Necklace 2) = {[0 ,0 ],[1,1]}
proof
A22: id the carrier of (Necklace 2) c= {[0 ,0 ],[1,1]}
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in id the carrier of (Necklace 2) or x in {[0 ,0 ],[1,1]} )
assume A23: x in id the carrier of (Necklace 2) ; :: thesis: x in {[0 ,0 ],[1,1]}
then consider x1, x2 being set such that
A24: x = [x1,x2] by RELAT_1:def 1;
A25: ( x1 in {0 ,1} & x1 = x2 ) by A20, A23, A24, RELAT_1:def 10;
then ( x1 = 0 or x1 = 1 ) by TARSKI:def 2;
hence x in {[0 ,0 ],[1,1]} by A24, A25, TARSKI:def 2; :: thesis: verum
end;
{[0 ,0 ],[1,1]} c= id the carrier of (Necklace 2)
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in {[0 ,0 ],[1,1]} or x in id the carrier of (Necklace 2) )
assume x in {[0 ,0 ],[1,1]} ; :: thesis: x in id the carrier of (Necklace 2)
then A26: ( x = [0 ,0 ] or x = [1,1] ) by TARSKI:def 2;
( 0 in the carrier of (Necklace 2) & 1 in the carrier of (Necklace 2) ) by A20, TARSKI:def 2;
hence x in id the carrier of (Necklace 2) by A26, RELAT_1:def 10; :: thesis: verum
end;
hence id the carrier of (Necklace 2) = {[0 ,0 ],[1,1]} by A22, XBOOLE_0:def 10; :: thesis: verum
end;
the InternalRel of (Necklace 2) ` = id the carrier of (Necklace 2)
proof
thus the InternalRel of (Necklace 2) ` c= id the carrier of (Necklace 2) :: according to XBOOLE_0:def 10 :: thesis: id the carrier of (Necklace 2) c= the InternalRel of (Necklace 2) `
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in the InternalRel of (Necklace 2) ` or x in id the carrier of (Necklace 2) )
assume x in the InternalRel of (Necklace 2) ` ; :: thesis: x in id the carrier of (Necklace 2)
then A27: ( x in [:the carrier of (Necklace 2),the carrier of (Necklace 2):] & not x in the InternalRel of (Necklace 2) ) by XBOOLE_0:def 5;
then x in {[0 ,0 ],[0 ,1],[1,0 ],[1,1]} by A20, MCART_1:25;
then ( x = [0 ,0 ] or x = [0 ,1] or x = [1,0 ] or x = [1,1] ) by ENUMSET1:def 2;
hence x in id the carrier of (Necklace 2) by A17, A21, A27, TARSKI:def 2; :: thesis: verum
end;
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in id the carrier of (Necklace 2) or x in the InternalRel of (Necklace 2) ` )
assume A28: x in id the carrier of (Necklace 2) ; :: thesis: x in the InternalRel of (Necklace 2) `
then A29: ( x = [0 ,0 ] or x = [1,1] ) by A21, TARSKI:def 2;
not x in the InternalRel of (Necklace 2) then ( x in {[0 ,0 ],[0 ,1],[1,0 ],[1,1]} & not x in the InternalRel of (Necklace 2) ) by A29, ENUMSET1:def 2;
then ( x in [:the carrier of (Necklace 2),the carrier of (Necklace 2):] & not x in the InternalRel of (Necklace 2) ) by A20, MCART_1:25;
hence x in the InternalRel of (Necklace 2) ` by XBOOLE_0:def 5; :: thesis: verum
end;
hence contradiction by A19; :: thesis: verum
end;
hence contradiction by A1, A3, A4, Th18, CARD_1:47; :: thesis: verum
end;
suppose A34: n = 3 ; :: thesis: contradiction
set S = Necklace 3;
set T = ComplRelStr (Necklace 3);
set X = {[0 ,1],[1,0 ],[1,2],[2,1]};
set Y = the InternalRel of (Necklace 3);
A35: the carrier of (Necklace 3) = {0 ,1,2} by Th21, YELLOW11:1;
A36: card the InternalRel of (Necklace 3) = 2 * (3 - 1) by Th28
.= 4 ;
A37: the InternalRel of (Necklace 3) = { [i,(i + 1)] where i is Element of NAT : i + 1 < 3 } \/ { [(i + 1),i] where i is Element of NAT : i + 1 < 3 } by Th19;
A38: [0 ,(0 + 1)] in { [i,(i + 1)] where i is Element of NAT : i + 1 < 3 } ;
A39: [(0 + 1),0 ] in { [(i + 1),i] where i is Element of NAT : i + 1 < 3 } ;
A40: [(0 + 1),(1 + 1)] in { [i,(i + 1)] where i is Element of NAT : i + 1 < 3 } ;
A41: [(1 + 1),(0 + 1)] in { [(i + 1),i] where i is Element of NAT : i + 1 < 3 } ;
A42: {[0 ,1],[1,0 ],[1,2],[2,1]} c= the InternalRel of (Necklace 3)
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in {[0 ,1],[1,0 ],[1,2],[2,1]} or x in the InternalRel of (Necklace 3) )
assume A43: x in {[0 ,1],[1,0 ],[1,2],[2,1]} ; :: thesis: x in the InternalRel of (Necklace 3)
end;
the InternalRel of (Necklace 3) c= {[0 ,1],[1,0 ],[1,2],[2,1]}
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in the InternalRel of (Necklace 3) or x in {[0 ,1],[1,0 ],[1,2],[2,1]} )
assume A44: x in the InternalRel of (Necklace 3) ; :: thesis: x in {[0 ,1],[1,0 ],[1,2],[2,1]}
then consider y, z being set such that
A45: x = [y,z] by RELAT_1:def 1;
per cases ( x in { [i,(i + 1)] where i is Element of NAT : i + 1 < 3 } or x in { [(i + 1),i] where i is Element of NAT : i + 1 < 3 } ) by A37, A44, XBOOLE_0:def 3;
suppose x in { [i,(i + 1)] where i is Element of NAT : i + 1 < 3 } ; :: thesis: x in {[0 ,1],[1,0 ],[1,2],[2,1]}
then consider i being Element of NAT such that
A46: ( [y,z] = [i,(i + 1)] & i + 1 < 3 ) by A45;
A47: ( y = i & z = i + 1 ) by A46, ZFMISC_1:33;
i + 1 < 1 + 2 by A46;
then i < 1 + 1 by XREAL_1:9;
then i <= 1 by NAT_1:13;
then ( y = 0 or y = 1 ) by A47, NAT_1:26;
hence x in {[0 ,1],[1,0 ],[1,2],[2,1]} by A45, A47, ENUMSET1:def 2; :: thesis: verum
end;
suppose x in { [(i + 1),i] where i is Element of NAT : i + 1 < 3 } ; :: thesis: x in {[0 ,1],[1,0 ],[1,2],[2,1]}
then consider i being Element of NAT such that
A48: ( [y,z] = [(i + 1),i] & i + 1 < 3 ) by A45;
A49: ( y = i + 1 & z = i ) by A48, ZFMISC_1:33;
i + 1 < 1 + 2 by A48;
then i < 1 + 1 by XREAL_1:9;
then i <= 1 by NAT_1:13;
then ( z = 0 or z = 1 ) by A49, NAT_1:26;
hence x in {[0 ,1],[1,0 ],[1,2],[2,1]} by A45, A49, ENUMSET1:def 2; :: thesis: verum
end;
end;
end;
then A50: {[0 ,1],[1,0 ],[1,2],[2,1]} = the InternalRel of (Necklace 3) by A42, XBOOLE_0:def 10;
A51: id the carrier of (Necklace 3) = {[0 ,0 ],[1,1],[2,2]}
proof
A52: id the carrier of (Necklace 3) c= {[0 ,0 ],[1,1],[2,2]}
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in id the carrier of (Necklace 3) or x in {[0 ,0 ],[1,1],[2,2]} )
assume A53: x in id the carrier of (Necklace 3) ; :: thesis: x in {[0 ,0 ],[1,1],[2,2]}
then consider x1, x2 being set such that
A54: x = [x1,x2] by RELAT_1:def 1;
A55: ( x1 in {0 ,1,2} & x1 = x2 ) by A35, A53, A54, RELAT_1:def 10;
then ( x1 = 0 or x1 = 1 or x1 = 2 ) by ENUMSET1:def 1;
hence x in {[0 ,0 ],[1,1],[2,2]} by A54, A55, ENUMSET1:def 1; :: thesis: verum
end;
{[0 ,0 ],[1,1],[2,2]} c= id the carrier of (Necklace 3)
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in {[0 ,0 ],[1,1],[2,2]} or x in id the carrier of (Necklace 3) )
assume A56: x in {[0 ,0 ],[1,1],[2,2]} ; :: thesis: x in id the carrier of (Necklace 3)
per cases ( x = [0 ,0 ] or x = [1,1] or x = [2,2] ) by A56, ENUMSET1:def 1;
end;
end;
hence id the carrier of (Necklace 3) = {[0 ,0 ],[1,1],[2,2]} by A52, XBOOLE_0:def 10; :: thesis: verum
end;
A59: the InternalRel of (ComplRelStr (Necklace 3)) = (the InternalRel of (Necklace 3) ` ) \ (id the carrier of (Necklace 3)) by Def9;
A60: [:the carrier of (Necklace 3),the carrier of (Necklace 3):] = {[0 ,0 ],[0 ,1],[0 ,2],[1,0 ],[1,1],[1,2],[2,0 ],[2,1],[2,2]} by A35, Th3;
A61: the InternalRel of (Necklace 3) ` = {[0 ,2],[2,0 ],[0 ,0 ],[1,1],[2,2]}
proof
thus the InternalRel of (Necklace 3) ` c= {[0 ,2],[2,0 ],[0 ,0 ],[1,1],[2,2]} :: according to XBOOLE_0:def 10 :: thesis: {[0 ,2],[2,0 ],[0 ,0 ],[1,1],[2,2]} c= the InternalRel of (Necklace 3) `
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in the InternalRel of (Necklace 3) ` or x in {[0 ,2],[2,0 ],[0 ,0 ],[1,1],[2,2]} )
assume x in the InternalRel of (Necklace 3) ` ; :: thesis: x in {[0 ,2],[2,0 ],[0 ,0 ],[1,1],[2,2]}
then ( x in {[0 ,0 ],[0 ,1],[0 ,2],[1,0 ],[1,1],[1,2],[2,0 ],[2,1],[2,2]} & not x in {[0 ,1],[1,0 ],[1,2],[2,1]} ) by A42, A60, XBOOLE_0:def 5;
then ( x in {[0 ,0 ],[0 ,1],[0 ,2],[1,0 ],[1,1],[1,2],[2,0 ],[2,1],[2,2]} & x <> [0 ,1] & x <> [1,0 ] & x <> [1,2] & x <> [2,1] ) by ENUMSET1:def 2;
then ( x = [0 ,2] or x = [2,0 ] or x = [0 ,0 ] or x = [1,1] or x = [2,2] ) by ENUMSET1:def 7;
hence x in {[0 ,2],[2,0 ],[0 ,0 ],[1,1],[2,2]} by ENUMSET1:def 3; :: thesis: verum
end;
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in {[0 ,2],[2,0 ],[0 ,0 ],[1,1],[2,2]} or x in the InternalRel of (Necklace 3) ` )
assume x in {[0 ,2],[2,0 ],[0 ,0 ],[1,1],[2,2]} ; :: thesis: x in the InternalRel of (Necklace 3) `
then A62: ( x = [0 ,2] or x = [2,0 ] or x = [0 ,0 ] or x = [1,1] or x = [2,2] ) by ENUMSET1:def 3;
then ( x <> [0 ,1] & x <> [1,0 ] & x <> [1,2] & x <> [2,1] ) by ZFMISC_1:33;
then A63: not x in {[0 ,1],[1,0 ],[1,2],[2,1]} by ENUMSET1:def 2;
x in {[0 ,0 ],[0 ,1],[0 ,2],[1,0 ],[1,1],[1,2],[2,0 ],[2,1],[2,2]} by A62, ENUMSET1:def 7;
hence x in the InternalRel of (Necklace 3) ` by A50, A60, A63, XBOOLE_0:def 5; :: thesis: verum
end;
A64: the InternalRel of (ComplRelStr (Necklace 3)) = {[0 ,2],[2,0 ]}
proof
thus the InternalRel of (ComplRelStr (Necklace 3)) c= {[0 ,2],[2,0 ]} :: according to XBOOLE_0:def 10 :: thesis: {[0 ,2],[2,0 ]} c= the InternalRel of (ComplRelStr (Necklace 3))
proof
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in the InternalRel of (ComplRelStr (Necklace 3)) or x in {[0 ,2],[2,0 ]} )
assume x in the InternalRel of (ComplRelStr (Necklace 3)) ; :: thesis: x in {[0 ,2],[2,0 ]}
then A65: ( x in {[0 ,2],[2,0 ],[0 ,0 ],[1,1],[2,2]} & not x in {[0 ,0 ],[1,1],[2,2]} ) by A51, A59, A61, XBOOLE_0:def 5;
then ( x = [0 ,2] or x = [2,0 ] or x = [0 ,0 ] or x = [1,1] or x = [2,2] ) by ENUMSET1:def 3;
hence x in {[0 ,2],[2,0 ]} by A65, ENUMSET1:def 1, TARSKI:def 2; :: thesis: verum
end;
let x be set ; :: according to TARSKI:def 3 :: thesis: ( not x in {[0 ,2],[2,0 ]} or x in the InternalRel of (ComplRelStr (Necklace 3)) )
assume x in {[0 ,2],[2,0 ]} ; :: thesis: x in the InternalRel of (ComplRelStr (Necklace 3))
then A66: ( x = [0 ,2] or x = [2,0 ] ) by TARSKI:def 2;
then A67: x in {[0 ,2],[2,0 ],[0 ,0 ],[1,1],[2,2]} by ENUMSET1:def 3;
( x <> [0 ,0 ] & x <> [1,1] & x <> [2,2] ) by A66, ZFMISC_1:33;
then not x in {[0 ,0 ],[1,1],[2,2]} by ENUMSET1:def 1;
hence x in the InternalRel of (ComplRelStr (Necklace 3)) by A51, A59, A61, A67, XBOOLE_0:def 5; :: thesis: verum
end;
[0 ,2] <> [2,0 ] by ZFMISC_1:33;
then card the InternalRel of (ComplRelStr (Necklace 3)) = 2 by A64, CARD_2:76;
hence contradiction by A1, A34, A36, Th18; :: thesis: verum
end;
suppose A68: n > 4 ; :: thesis: contradiction
set S = Necklace n;
set T = ComplRelStr (Necklace n);
A69: the carrier of (Necklace n) = n by Th21;
A70: card the InternalRel of (Necklace n) = 2 * (n - 1) by A68, Th28;
A71: the carrier of (Necklace n) = n by Th21;
card n = n by CARD_1:def 5;
then card [:n,n:] = n * n by CARD_2:65;
then A72: card (the InternalRel of (Necklace n) ` ) = (n * n) - (2 * (n - 1)) by A70, A71, CARD_2:63;
n = card n by CARD_1:def 5;
then A73: card (id the carrier of (Necklace n)) = n by A69, Th6;
A74: id the carrier of (Necklace n) misses the InternalRel of (Necklace n)
proof
assume not id the carrier of (Necklace n) misses the InternalRel of (Necklace n) ; :: thesis: contradiction
then consider x being set such that
A75: x in id the carrier of (Necklace n) and
A76: x in the InternalRel of (Necklace n) by XBOOLE_0:3;
consider x1, x2 being set such that
A77: x = [x1,x2] by A75, RELAT_1:def 1;
A78: x1 = x2 by A75, A77, RELAT_1:def 10;
consider i being Element of NAT such that
i + 1 < n and
A79: ( x = [i,(i + 1)] or x = [(i + 1),i] ) by A76, Th20;
per cases ( [x1,x2] = [i,(i + 1)] or [x1,x2] = [(i + 1),i] ) by A77, A79;
suppose [x1,x2] = [i,(i + 1)] ; :: thesis: contradiction
end;
suppose [x1,x2] = [(i + 1),i] ; :: thesis: contradiction
end;
end;
end;
A80: card the InternalRel of (ComplRelStr (Necklace n)) = card ((the InternalRel of (Necklace n) ` ) \ (id the carrier of (Necklace n))) by Def9
.= ((n * n) - (2 * (n - 1))) - n by A72, A73, A74, CARD_2:63, XBOOLE_1:86 ;
((n * n) - (2 * (n - 1))) - n <> 2 * (n - 1)
proof
assume not ((n * n) - (2 * (n - 1))) - n <> 2 * (n - 1) ; :: thesis: contradiction
then A81: ((1 * (n ^2 )) + ((- 5) * n)) + 4 = 0 ;
A82: delta 1,(- 5),4 = ((- 5) ^2 ) - ((4 * 1) * 4) by QUIN_1:def 1
.= 9 ;
then ( n = ((- (- 5)) - (sqrt (delta 1,(- 5),4))) / (2 * 1) or n = ((- (- 5)) + (sqrt (delta 1,(- 5),4))) / (2 * 1) ) by A81, QUIN_1:15;
then ( n = (5 - (sqrt (3 ^2 ))) / 2 or n = (5 + (sqrt (3 ^2 ))) / 2 ) by A82;
then A83: ( n = (5 - 3) / 2 or n = (5 + 3) / 2 ) by SQUARE_1:89;
end;
hence contradiction by A1, A70, A80, Th18; :: thesis: verum
end;
end;