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{{Knot Navigation Links|ext=gif}}
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{{Rolfsen Knot Page Header|n=8|k=8|KnotilusURL=http://srankin.math.uwo.ca/cgi-bin/retrieve.cgi/-1,8,-2,1,-4,5,-8,2,-6,7,-3,4,-5,3,-7,6/goTop.html}}
{| align=left
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|[[Image:{{PAGENAME}}.gif]]
|{{Rolfsen Knot Site Links|n=8|k=8|KnotilusURL=http://srankin.math.uwo.ca/cgi-bin/retrieve.cgi/-1,8,-2,1,-4,5,-8,2,-6,7,-3,4,-5,3,-7,6/goTop.html}}
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{{Vassiliev Invariants}}
{{Vassiliev Invariants}}


===[[Khovanov Homology]]===
{{Khovanov Homology|table=<table border=1>

The coefficients of the monomials <math>t^rq^j</math> are shown, along with their alternating sums <math>\chi</math> (fixed <math>j</math>, alternation over <math>r</math>). The squares with <font class=HLYellow>yellow</font> highlighting are those on the "critical diagonals", where <math>j-2r=s+1</math> or <math>j-2r=s+1</math>, where <math>s=</math>{{Data:{{PAGENAME}}/Signature}} is the signature of {{PAGENAME}}. Nonzero entries off the critical diagonals (if any exist) are highlighted in <font class=HLRed>red</font>.

<center><table border=1>
<tr align=center>
<tr align=center>
<td width=15.3846%><table cellpadding=0 cellspacing=0>
<td width=15.3846%><table cellpadding=0 cellspacing=0>
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<tr align=center><td>-5</td><td bgcolor=yellow>&nbsp;</td><td bgcolor=yellow>1</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>1</td></tr>
<tr align=center><td>-5</td><td bgcolor=yellow>&nbsp;</td><td bgcolor=yellow>1</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>1</td></tr>
<tr align=center><td>-7</td><td bgcolor=yellow>1</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>-1</td></tr>
<tr align=center><td>-7</td><td bgcolor=yellow>1</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>&nbsp;</td><td>-1</td></tr>
</table></center>
</table>}}

{{Computer Talk Header}}
{{Computer Talk Header}}


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2 q t + 2 q t + q t + 2 q t + q t + q t + q t</nowiki></pre></td></tr>
2 q t + 2 q t + q t + 2 q t + q t + q t + q t</nowiki></pre></td></tr>
</table>
</table>

[[Category:Knot Page]]

Revision as of 20:11, 28 August 2005

8 7.gif

8_7

8 9.gif

8_9

8 8.gif Visit 8 8's page at the Knot Server (KnotPlot driven, includes 3D interactive images!)

Visit 8 8's page at Knotilus!

Visit 8 8's page at the original Knot Atlas!

8 8 Quick Notes


8 8 Further Notes and Views

Knot presentations

Planar diagram presentation X1425 X3849 X11,15,12,14 X5,13,6,12 X13,7,14,6 X9,1,10,16 X15,11,16,10 X7283
Gauss code -1, 8, -2, 1, -4, 5, -8, 2, -6, 7, -3, 4, -5, 3, -7, 6
Dowker-Thistlethwaite code 4 8 12 2 16 14 6 10
Conway Notation [2312]

Three dimensional invariants

Symmetry type Reversible
Unknotting number 2
3-genus 2
Bridge index 2
Super bridge index
Nakanishi index 1
Maximal Thurston-Bennequin number [-4][-6]
Hyperbolic Volume 7.80134
A-Polynomial See Data:8 8/A-polynomial

[edit Notes for 8 8's three dimensional invariants]

Four dimensional invariants

Smooth 4 genus
Topological 4 genus
Concordance genus
Rasmussen s-Invariant 0

[edit Notes for 8 8's four dimensional invariants]

Polynomial invariants

Alexander polynomial
Conway polynomial
2nd Alexander ideal (db, data sources)
Determinant and Signature { 25, 0 }
Jones polynomial
HOMFLY-PT polynomial (db, data sources)
Kauffman polynomial (db, data sources)
The A2 invariant
The G2 invariant

Vassiliev invariants

V2 and V3: (2, 1)
V2,1 through V6,9:
V2,1 V3,1 V4,1 V4,2 V4,3 V5,1 V5,2 V5,3 V5,4 V6,1 V6,2 V6,3 V6,4 V6,5 V6,6 V6,7 V6,8 V6,9

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 0 is the signature of 8 8. Nonzero entries off the critical diagonals (if any exist) are highlighted in red.   
\ r
  \  
j \
-3-2-1012345χ
11        1-1
9       1 1
7      21 -1
5     21  1
3    22   0
1   32    1
-1  13     2
-3 12      -1
-5 1       1
-71        -1
Integral Khovanov Homology

(db, data source)

  

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[8, 8]]
Out[2]=  
8
In[3]:=
PD[Knot[8, 8]]
Out[3]=  
PD[X[1, 4, 2, 5], X[3, 8, 4, 9], X[11, 15, 12, 14], X[5, 13, 6, 12], 
  X[13, 7, 14, 6], X[9, 1, 10, 16], X[15, 11, 16, 10], X[7, 2, 8, 3]]
In[4]:=
GaussCode[Knot[8, 8]]
Out[4]=  
GaussCode[-1, 8, -2, 1, -4, 5, -8, 2, -6, 7, -3, 4, -5, 3, -7, 6]
In[5]:=
BR[Knot[8, 8]]
Out[5]=  
BR[4, {1, 1, 1, 2, -1, -3, 2, -3, -3}]
In[6]:=
alex = Alexander[Knot[8, 8]][t]
Out[6]=  
    2    6            2

9 + -- - - - 6 t + 2 t

    2   t
t
In[7]:=
Conway[Knot[8, 8]][z]
Out[7]=  
       2      4
1 + 2 z  + 2 z
In[8]:=
Select[AllKnots[], (alex === Alexander[#][t])&]
Out[8]=  
{Knot[8, 8], Knot[10, 129], Knot[11, NonAlternating, 39], 
 Knot[11, NonAlternating, 45], Knot[11, NonAlternating, 50], 

Knot[11, NonAlternating, 132]}
In[9]:=
{KnotDet[Knot[8, 8]], KnotSignature[Knot[8, 8]]}
Out[9]=  
{25, 0}
In[10]:=
J=Jones[Knot[8, 8]][q]
Out[10]=  
     -3   2    3            2      3      4    5

5 - q + -- - - - 4 q + 4 q - 3 q + 2 q - q

          2   q
q
In[11]:=
Select[AllKnots[], (J === Jones[#][q] || (J /. q-> 1/q) === Jones[#][q])&]
Out[11]=  
{Knot[8, 8], Knot[10, 129]}
In[12]:=
A2Invariant[Knot[8, 8]][q]
Out[12]=  
     -10    -4   2       2    4    8    10    16

1 - q - q + -- + 2 q + q + q - q - q

                 2
q
In[13]:=
Kauffman[Knot[8, 8]][a, z]
Out[13]=  
                                                          2      2
    -4    -2    2   2 z   3 z   z          3      2   4 z    5 z

2 - a - a + a + --- + --- + - - a z - a z - z + ---- + ---- -

                     5     3    a                       4      2
                    a     a                            a      a

              3      3      3                   4      4
    2  2   3 z    5 z    3 z     3  3    4   6 z    9 z       2  4
 2 a  z  - ---- - ---- - ---- + a  z  - z  - ---- - ---- + 2 a  z  + 
             5      3     a                    4      2
            a      a                          a      a

  5    5                      6      6    7    7
 z    z         5      6   2 z    4 z    z    z
 -- + -- + 2 a z  + 2 z  + ---- + ---- + -- + --
  5   a                      4      2     3   a
a a a a
In[14]:=
{Vassiliev[2][Knot[8, 8]], Vassiliev[3][Knot[8, 8]]}
Out[14]=  
{0, 1}
In[15]:=
Kh[Knot[8, 8]][q, t]
Out[15]=  
3           1       1       1      2      1               3

- + 3 q + ----- + ----- + ----- + ---- + --- + 2 q t + 2 q t + q 7 3 5 2 3 2 3 q t

         q  t    q  t    q  t    q  t

    3  2      5  2    5  3      7  3    7  4    9  4    11  5
2 q t + 2 q t + q t + 2 q t + q t + q t + q t