8 13

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8_12

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8_14

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8 13 Quick Notes


8 13 Further Notes and Views

Knot presentations

Planar diagram presentation X1425 X3,10,4,11 X11,1,12,16 X5,13,6,12 X15,7,16,6 X7,15,8,14 X13,9,14,8 X9,2,10,3
Gauss code -1, 8, -2, 1, -4, 5, -6, 7, -8, 2, -3, 4, -7, 6, -5, 3
Dowker-Thistlethwaite code 4 10 12 14 2 16 8 6
Conway Notation [31112]

Three dimensional invariants

Symmetry type Reversible
Unknotting number 1
3-genus 2
Bridge index 2
Super bridge index
Nakanishi index 1
Maximal Thurston-Bennequin number [-4][-6]
Hyperbolic Volume 8.53123
A-Polynomial See Data:8 13/A-polynomial

[edit Notes for 8 13's three dimensional invariants]

Four dimensional invariants

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

[edit Notes for 8 13's four dimensional invariants]

Polynomial invariants

Alexander polynomial
Conway polynomial
2nd Alexander ideal (db, data sources)
Determinant and Signature { 29, 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: (1, 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 13. 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     31  2
3    22   0
1   33    0
-1  23     1
-3 12      -1
-5 2       2
-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, 13]]
Out[2]=  
8
In[3]:=
PD[Knot[8, 13]]
Out[3]=  
PD[X[1, 4, 2, 5], X[3, 10, 4, 11], X[11, 1, 12, 16], X[5, 13, 6, 12], 
  X[15, 7, 16, 6], X[7, 15, 8, 14], X[13, 9, 14, 8], X[9, 2, 10, 3]]
In[4]:=
GaussCode[Knot[8, 13]]
Out[4]=  
GaussCode[-1, 8, -2, 1, -4, 5, -6, 7, -8, 2, -3, 4, -7, 6, -5, 3]
In[5]:=
BR[Knot[8, 13]]
Out[5]=  
BR[4, {-1, -1, 2, -1, 2, 2, 3, -2, 3}]
In[6]:=
alex = Alexander[Knot[8, 13]][t]
Out[6]=  
     2    7            2

11 + -- - - - 7 t + 2 t

     2   t
t
In[7]:=
Conway[Knot[8, 13]][z]
Out[7]=  
     2      4
1 + z  + 2 z
In[8]:=
Select[AllKnots[], (alex === Alexander[#][t])&]
Out[8]=  
{Knot[8, 13]}
In[9]:=
{KnotDet[Knot[8, 13]], KnotSignature[Knot[8, 13]]}
Out[9]=  
{29, 0}
In[10]:=
J=Jones[Knot[8, 13]][q]
Out[10]=  
     -3   3    4            2      3      4    5

5 - q + -- - - - 5 q + 5 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, 13]}
In[12]:=
A2Invariant[Knot[8, 13]][q]
Out[12]=  
      -10    -8    -6    -4    -2    2    4    6      8    10    16
-1 - q    + q   + q   - q   + q   + q  + q  + q  + 2 q  - q   - q
In[13]:=
Kauffman[Knot[8, 13]][a, z]
Out[13]=  
                                       2      2                3
 -4   2    2 z   4 z   3 z         5 z    7 z       2  2   3 z

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

       2    5     3     a            4      2                5
      a    a     a                  a      a                a

    3      3                              4       4              5
 7 z    9 z         3    3  3      4   6 z    11 z       2  4   z
 ---- - ---- - 4 a z  + a  z  - 2 z  - ---- - ----- + 3 a  z  + -- + 
   3     a                               4      2                5
  a                                     a      a                a

  5      5                      6      6    7    7
 z    4 z         5      6   2 z    5 z    z    z
 -- + ---- + 4 a z  + 3 z  + ---- + ---- + -- + --
  3    a                       4      2     3   a
a a a a
In[14]:=
{Vassiliev[2][Knot[8, 13]], Vassiliev[3][Knot[8, 13]]}
Out[14]=  
{0, 1}
In[15]:=
Kh[Knot[8, 13]][q, t]
Out[15]=  
3           1       2       1      2      2               3

- + 3 q + ----- + ----- + ----- + ---- + --- + 3 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 + 3 q t + q t + 2 q t + q t + q t + q t