9 7
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Visit 9 7's page at the Knot Server (KnotPlot driven, includes 3D interactive images!)
Visit 9 7's page at Knotilus! Visit 9 7's page at the original Knot Atlas! |
9 7 Quick Notes |
Knot presentations
Planar diagram presentation | X1425 X3,12,4,13 X5,16,6,17 X7,18,8,1 X17,6,18,7 X9,14,10,15 X13,10,14,11 X15,8,16,9 X11,2,12,3 |
Gauss code | -1, 9, -2, 1, -3, 5, -4, 8, -6, 7, -9, 2, -7, 6, -8, 3, -5, 4 |
Dowker-Thistlethwaite code | 4 12 16 18 14 2 10 8 6 |
Conway Notation | [342] |
Three dimensional invariants
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Four dimensional invariants
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Polynomial invariants
A1 Invariants.
Weight | Invariant |
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1 | |
2 | |
3 | |
4 | |
5 |
A2 Invariants.
Weight | Invariant |
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1,0 | |
1,1 | |
2,0 |
A3 Invariants.
Weight | Invariant |
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0,1,0 | |
1,0,0 |
A4 Invariants.
Weight | Invariant |
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0,1,0,0 | |
1,0,0,0 |
B2 Invariants.
Weight | Invariant |
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0,1 | |
1,0 |
D4 Invariants.
Weight | Invariant |
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1,0,0,0 |
G2 Invariants.
Weight | Invariant |
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1,0 |
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KnotTheory`
, as shown in the (simulated) Mathematica session below. Your input (in red) is realistic; all else should have the same content as in a real mathematica session, but with different formatting. This Mathematica session is also available (albeit only for the knot 5_2) as the notebook PolynomialInvariantsSession.nb.
(The path below may be different on your system, and possibly also the KnotTheory` date)
In[1]:=
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AppendTo[$Path, "C:/drorbn/projects/KAtlas/"];
<< KnotTheory`
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Loading KnotTheory` version of August 31, 2006, 11:25:27.5625.
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In[3]:=
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K = Knot["9 7"];
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In[4]:=
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Alexander[K][t]
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KnotTheory::loading: Loading precomputed data in PD4Knots`.
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Out[4]=
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In[5]:=
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Conway[K][z]
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Out[5]=
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In[6]:=
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Alexander[K, 2][t]
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KnotTheory::credits: The program Alexander[K, r] to compute Alexander ideals was written by Jana Archibald at the University of Toronto in the summer of 2005.
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Out[6]=
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In[7]:=
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{KnotDet[K], KnotSignature[K]}
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Out[7]=
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{ 29, -4 } |
In[8]:=
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Jones[K][q]
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KnotTheory::loading: Loading precomputed data in Jones4Knots`.
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Out[8]=
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In[9]:=
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HOMFLYPT[K][a, z]
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KnotTheory::credits: The HOMFLYPT program was written by Scott Morrison.
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Out[9]=
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In[10]:=
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Kauffman[K][a, z]
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KnotTheory::loading: Loading precomputed data in Kauffman4Knots`.
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Out[10]=
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Vassiliev invariants
V2 and V3: | (5, -12) |
V2,1 through V6,9: |
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V2,1 through V6,9 were provided by Petr Dunin-Barkowski <barkovs@itep.ru>, Andrey Smirnov <asmirnov@itep.ru>, and Alexei Sleptsov <sleptsov@itep.ru> and uploaded on October 2010 by User:Drorbn. Note that they are normalized differently than V2 and V3.
Khovanov Homology
The coefficients of the monomials are shown, along with their alternating sums (fixed , alternation over ). The squares with yellow highlighting are those on the "critical diagonals", where or , where -4 is the signature of 9 7. Nonzero entries off the critical diagonals (if any exist) are highlighted in red.
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-9 | -8 | -7 | -6 | -5 | -4 | -3 | -2 | -1 | 0 | χ | |||||||||
-3 | 1 | 1 | ||||||||||||||||||
-5 | 1 | 1 | 0 | |||||||||||||||||
-7 | 2 | 2 | ||||||||||||||||||
-9 | 2 | 1 | -1 | |||||||||||||||||
-11 | 3 | 2 | 1 | |||||||||||||||||
-13 | 2 | 2 | 0 | |||||||||||||||||
-15 | 2 | 3 | -1 | |||||||||||||||||
-17 | 1 | 2 | 1 | |||||||||||||||||
-19 | 1 | 2 | -1 | |||||||||||||||||
-21 | 1 | 1 | ||||||||||||||||||
-23 | 1 | -1 |
Computer Talk
Much of the above data can be recomputed by Mathematica using the package KnotTheory`
. See A Sample KnotTheory` Session.
In[1]:= |
<< KnotTheory` |
Loading KnotTheory` (version of August 17, 2005, 14:44:34)... | |
In[2]:= | Crossings[Knot[9, 7]] |
Out[2]= | 9 |
In[3]:= | PD[Knot[9, 7]] |
Out[3]= | PD[X[1, 4, 2, 5], X[3, 12, 4, 13], X[5, 16, 6, 17], X[7, 18, 8, 1],X[17, 6, 18, 7], X[9, 14, 10, 15], X[13, 10, 14, 11],X[15, 8, 16, 9], X[11, 2, 12, 3]] |
In[4]:= | GaussCode[Knot[9, 7]] |
Out[4]= | GaussCode[-1, 9, -2, 1, -3, 5, -4, 8, -6, 7, -9, 2, -7, 6, -8, 3, -5, 4] |
In[5]:= | BR[Knot[9, 7]] |
Out[5]= | BR[4, {-1, -1, -1, -1, -2, 1, -2, -3, 2, -3, -3}] |
In[6]:= | alex = Alexander[Knot[9, 7]][t] |
Out[6]= | 3 7 2 |
In[7]:= | Conway[Knot[9, 7]][z] |
Out[7]= | 2 4 1 + 5 z + 3 z |
In[8]:= | Select[AllKnots[], (alex === Alexander[#][t])&] |
Out[8]= | {Knot[9, 7]} |
In[9]:= | {KnotDet[Knot[9, 7]], KnotSignature[Knot[9, 7]]} |
Out[9]= | {29, -4} |
In[10]:= | J=Jones[Knot[9, 7]][q] |
Out[10]= | -11 2 3 4 5 5 4 3 -3 -2 |
In[11]:= | Select[AllKnots[], (J === Jones[#][q] || (J /. q-> 1/q) === Jones[#][q])&] |
Out[11]= | {Knot[9, 7]} |
In[12]:= | A2Invariant[Knot[9, 7]][q] |
Out[12]= | -34 -28 -26 -18 -16 -12 2 -6 |
In[13]:= | Kauffman[Knot[9, 7]][a, z] |
Out[13]= | 4 6 8 10 5 7 9 11 13 |
In[14]:= | {Vassiliev[2][Knot[9, 7]], Vassiliev[3][Knot[9, 7]]} |
Out[14]= | {0, -12} |
In[15]:= | Kh[Knot[9, 7]][q, t] |
Out[15]= | -5 -3 1 1 1 2 1 2 |