7 6

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7 5.gif

7_5

7 7.gif

7_7

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7 6 Quick Notes


7 6 Further Notes and Views

Knot presentations

Planar diagram presentation X1425 X3849 X5,12,6,13 X9,1,10,14 X13,11,14,10 X11,6,12,7 X7283
Gauss code -1, 7, -2, 1, -3, 6, -7, 2, -4, 5, -6, 3, -5, 4
Dowker-Thistlethwaite code 4 8 12 2 14 6 10
Conway Notation [2212]

Three dimensional invariants

Symmetry type Reversible
Unknotting number 1
3-genus 2
Bridge index 2
Super bridge index 4
Nakanishi index 1
Maximal Thurston-Bennequin number [-8][-1]
Hyperbolic Volume 7.08493
A-Polynomial See Data:7 6/A-polynomial

[edit Notes for 7 6's three dimensional invariants]

Four dimensional invariants

Smooth 4 genus
Topological 4 genus
Concordance genus
Rasmussen s-Invariant -2

[edit Notes for 7 6's four dimensional invariants]

Polynomial invariants

Alexander polynomial
Conway polynomial
2nd Alexander ideal (db, data sources)
Determinant and Signature { 19, -2 }
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, -2)
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 -2 is the signature of 7 6. Nonzero entries off the critical diagonals (if any exist) are highlighted in red.   
\ r
  \  
j \
-5-4-3-2-1012χ
3       11
1      1 -1
-1     21 1
-3    22  0
-5   21   1
-7  12    1
-9 12     -1
-11 1      1
-131       -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[7, 6]]
Out[2]=  
7
In[3]:=
PD[Knot[7, 6]]
Out[3]=  
PD[X[1, 4, 2, 5], X[3, 8, 4, 9], X[5, 12, 6, 13], X[9, 1, 10, 14], 
  X[13, 11, 14, 10], X[11, 6, 12, 7], X[7, 2, 8, 3]]
In[4]:=
GaussCode[Knot[7, 6]]
Out[4]=  
GaussCode[-1, 7, -2, 1, -3, 6, -7, 2, -4, 5, -6, 3, -5, 4]
In[5]:=
BR[Knot[7, 6]]
Out[5]=  
BR[4, {-1, -1, 2, -1, -3, 2, -3}]
In[6]:=
alex = Alexander[Knot[7, 6]][t]
Out[6]=  
      -2   5          2

-7 - t + - + 5 t - t

t
In[7]:=
Conway[Knot[7, 6]][z]
Out[7]=  
     2    4
1 + z  - z
In[8]:=
Select[AllKnots[], (alex === Alexander[#][t])&]
Out[8]=  
{Knot[7, 6], Knot[10, 133]}
In[9]:=
{KnotDet[Knot[7, 6]], KnotSignature[Knot[7, 6]]}
Out[9]=  
{19, -2}
In[10]:=
J=Jones[Knot[7, 6]][q]
Out[10]=  
      -6   2    3    4    3    3

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

           5    4    3    2   q
q q q q
In[11]:=
Select[AllKnots[], (J === Jones[#][q] || (J /. q-> 1/q) === Jones[#][q])&]
Out[11]=  
{Knot[7, 6]}
In[12]:=
A2Invariant[Knot[7, 6]][q]
Out[12]=  
  -20    -18    -16    -12    -10    -6    -4    -2    4
-q    - q    + q    + q    + q    + q   - q   + q   + q
In[13]:=
Kauffman[Knot[7, 6]][a, z]
Out[13]=  
     2      4    6            3      7        2      2  2      4  2

1 + a + 2 a + a + a z + 2 a z - a z - 2 z - 4 a z - 4 a z -

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

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

-- + - + ------ + ------ + ----- + ----- + ----- + ----- + ----- +

3   q    13  5    11  4    9  4    9  3    7  3    7  2    5  2

q q t q t q t q t q t q t q t

  1      2     t          3  2
 ---- + ---- + - + q t + q  t
  5      3     q
q t q t