© | Dror Bar-Natan: The Knot Atlas: Torus Knots:
T(7,3)
T(7,3)
T(15,2)
T(15,2)
T(5,4)
TubePlot
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   The 15-Crossing Torus Knot T(5,4)

Visit T(5,4)'s page at Knotilus!

Acknowledgement

PD Presentation: X17,25,18,24 X10,26,11,25 X3,27,4,26 X11,19,12,18 X4,20,5,19 X27,21,28,20 X5,13,6,12 X28,14,29,13 X21,15,22,14 X29,7,30,6 X22,8,23,7 X15,9,16,8 X23,1,24,30 X16,2,17,1 X9,3,10,2

Gauss Code: {14, 15, -3, -5, -7, 10, 11, 12, -15, -2, -4, 7, 8, 9, -12, -14, -1, 4, 5, 6, -9, -11, -13, 1, 2, 3, -6, -8, -10, 13}

Braid Representative:    

Alexander Polynomial: t-6 - t-5 + t-2 - 1 + t2 - t5 + t6

Conway Polynomial: 1 + 15z2 + 56z4 + 77z6 + 44z8 + 11z10 + z12

Other knots with the same Alexander/Conway Polynomial: {...}

Determinant and Signature: {5, 8}

Jones Polynomial: q6 + q8 + q10 - q11 - q13

Other knots (up to mirrors) with the same Jones Polynomial: {...}

Coloured Jones Polynomial (in the 3-dimensional representation of sl(2); n=2): q12 + q15 + q18 - q23 - q26 - q29 + q30 - q32 + q33 - q35 + q36 - q38 + q39

A2 (sl(3)) Invariant: q22 + q24 + 2q26 + 2q28 + 3q30 + 2q32 + q34 - q36 - 2q38 - 3q40 - 3q42 - 2q44 - q46 + q48 + q50 + q52

Kauffman Polynomial: - a-19z + a-18 - a-18z2 - 8a-17z + 14a-17z3 - 7a-17z5 + a-17z7 + 9a-16 - 22a-16z2 + 21a-16z4 - 8a-16z6 + a-16z8 - 28a-15z + 84a-15z3 - 91a-15z5 + 46a-15z7 - 11a-15z9 + a-15z11 + 21a-14 - 91a-14z2 + 154a-14z4 - 129a-14z6 + 56a-14z8 - 12a-14z10 + a-14z12 - 21a-13z + 70a-13z3 - 84a-13z5 + 45a-13z7 - 11a-13z9 + a-13z11 + 14a-12 - 70a-12z2 + 133a-12z4 - 121a-12z6 + 55a-12z8 - 12a-12z10 + a-12z12

V2 and V3, the type 2 and 3 Vassiliev invariants: {15, 50}

Khovanov Homology. The coefficients of the monomials trqj are shown, along with their alternating sums χ (fixed j, alternation over r). The squares with yellow highlighting are those on the "critical diagonals", where j-2r=s+1 or j-2r=s+1, where s=8 is the signature of T(5,4). Nonzero entries off the critical diagonals (if any exist) are highlighted in red.

\ r
  \  
j \
0123456789χ
27         1-1
25       1  -1
23     1 11 -1
21     11   0
19   11 1   1
17    1     1
15  1       1
131         1
111         1


Computer Talk. The data above can be recomputed by Mathematica using the package KnotTheory`. Following setup, the sample Mathematica session below reproduces most of the above data (Mathematica system prompts in blue, human input in red, Mathematica output in black):

In[1]:=    
<< KnotTheory`
Loading KnotTheory` (version of August 30, 2005, 10:15:35)...
In[2]:=
TubePlot[TorusKnot[5, 4]]
Out[2]=   
 -Graphics- 
In[3]:=
Crossings[TorusKnot[5, 4]]
Out[3]=   
15
In[4]:=
PD[TorusKnot[5, 4]]
Out[4]=   
PD[X[17, 25, 18, 24], X[10, 26, 11, 25], X[3, 27, 4, 26], X[11, 19, 12, 18], 
 
>   X[4, 20, 5, 19], X[27, 21, 28, 20], X[5, 13, 6, 12], X[28, 14, 29, 13], 
 
>   X[21, 15, 22, 14], X[29, 7, 30, 6], X[22, 8, 23, 7], X[15, 9, 16, 8], 
 
>   X[23, 1, 24, 30], X[16, 2, 17, 1], X[9, 3, 10, 2]]
In[5]:=
GaussCode[TorusKnot[5, 4]]
Out[5]=   
GaussCode[14, 15, -3, -5, -7, 10, 11, 12, -15, -2, -4, 7, 8, 9, -12, -14, -1, 
 
>   4, 5, 6, -9, -11, -13, 1, 2, 3, -6, -8, -10, 13]
In[6]:=
BR[TorusKnot[5, 4]]
Out[6]=   
BR[4, {1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3, 1, 2, 3}]
In[7]:=
alex = Alexander[TorusKnot[5, 4]][t]
Out[7]=   
      -6    -5    -2    2    5    6
-1 + t   - t   + t   + t  - t  + t
In[8]:=
Conway[TorusKnot[5, 4]][z]
Out[8]=   
        2       4       6       8       10    12
1 + 15 z  + 56 z  + 77 z  + 44 z  + 11 z   + z
In[9]:=
Select[AllKnots[], (alex === Alexander[#][t])&]
Out[9]=   
{}
In[10]:=
{KnotDet[TorusKnot[5, 4]], KnotSignature[TorusKnot[5, 4]]}
Out[10]=   
{5, 8}
In[11]:=
J=Jones[TorusKnot[5, 4]][q]
Out[11]=   
 6    8    10    11    13
q  + q  + q   - q   - q
In[12]:=
Select[AllKnots[], (J === Jones[#][q] || (J /. q-> 1/q) === Jones[#][q])&]
Out[12]=   
{}
In[13]:=
ColouredJones[TorusKnot[5, 4], 2][q]
Out[13]=   
 12    15    18    23    26    29    30    32    33    35    36    38    39
q   + q   + q   - q   - q   - q   + q   - q   + q   - q   + q   - q   + q
In[14]:=
A2Invariant[TorusKnot[5, 4]][q]
Out[14]=   
 22    24      26      28      30      32    34    36      38      40      42
q   + q   + 2 q   + 2 q   + 3 q   + 2 q   + q   - q   - 2 q   - 3 q   - 3 q   - 
 
       44    46    48    50    52
>   2 q   - q   + q   + q   + q
In[15]:=
Kauffman[TorusKnot[5, 4]][a, z]
Out[15]=   
                                                    2        2       2
 -18    9    21    14     z    8 z   28 z   21 z   z     22 z    91 z
a    + --- + --- + --- - --- - --- - ---- - ---- - --- - ----- - ----- - 
        16    14    12    19    17    15     13     18     16      14
       a     a     a     a     a     a      a      a      a       a
 
        2       3       3       3       4        4        4      5       5
    70 z    14 z    84 z    70 z    21 z    154 z    133 z    7 z    91 z
>   ----- + ----- + ----- + ----- + ----- + ------ + ------ - ---- - ----- - 
      12      17      15      13      16      14       12      17      15
     a       a       a       a       a       a        a       a       a
 
        5      6        6        6    7        7       7    8        8
    84 z    8 z    129 z    121 z    z     46 z    45 z    z     56 z
>   ----- - ---- - ------ - ------ + --- + ----- + ----- + --- + ----- + 
      13     16      14       12      17     15      13     16     14
     a      a       a        a       a      a       a      a      a
 
        8       9       9       10       10    11    11    12    12
    55 z    11 z    11 z    12 z     12 z     z     z     z     z
>   ----- - ----- - ----- - ------ - ------ + --- + --- + --- + ---
      12      15      13      14       12      15    13    14    12
     a       a       a       a        a       a     a     a     a
In[16]:=
{Vassiliev[2][TorusKnot[5, 4]], Vassiliev[3][TorusKnot[5, 4]]}
Out[16]=   
{15, 50}
In[17]:=
Kh[TorusKnot[5, 4]][q, t]
Out[17]=   
 11    13    15  2    19  3    17  4    19  4    21  5    23  5    19  6
q   + q   + q   t  + q   t  + q   t  + q   t  + q   t  + q   t  + q   t  + 
 
     21  6    23  7    25  7    23  8    27  9
>   q   t  + q   t  + q   t  + q   t  + q   t


Dror Bar-Natan: The Knot Atlas: Torus Knots: The Torus Knot T(5,4)
T(7,3)
T(7,3)
T(15,2)
T(15,2)