T(3,2)

T(3,2)

T(5,2)

Visit T(3,2)'s page at Knotilus! Visit $3$.$2$.html T(3,2)'s page at the original Knot Atlas! See 3_1.

T(3,2) Further Notes and Views

Knot presentations

Planar diagram presentation	X3146 X1524 X5362
Gauss code	-2, 3, -1, 2, -3, 1
Dowker-Thistlethwaite code	4 6 2
Conway Notation	Data:T(3,2)/Conway Notation

Knot presentations

Planar diagram presentation	X3146 X1524 X5362
Gauss code	$\{-2,3,-1,2,-3,1\}$
Dowker-Thistlethwaite code	4 6 2

Polynomial invariants

Alexander polynomial	$t-1+t^{-1}$
Conway polynomial	$z^{2}+1$
2nd Alexander ideal (db, data sources)	$\{1\}$
Determinant and Signature	{ 3, 2 }
Jones polynomial	$-q^{4}+q^{3}+q$
HOMFLY-PT polynomial (db, data sources)	$z^{2}a^{-2}+2a^{-2}-a^{-4}$
Kauffman polynomial (db, data sources)	$z^{2}a^{-2}+z^{2}a^{-4}+za^{-3}+za^{-5}-2a^{-2}-a^{-4}$
The A2 invariant	Data:T(3,2)/QuantumInvariant/A2/1,0
The G2 invariant	Data:T(3,2)/QuantumInvariant/G2/1,0

Further Quantum Invariants

T(3,2) Quantum Invariants.

Computer Talk

The above data is available with the Mathematica package 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]:=

AppendTo[$Path, "C:/drorbn/projects/KAtlas/"]; << KnotTheory`

Loading KnotTheory` version of August 31, 2006, 11:25:27.5625. Read more at http://katlas.math.toronto.edu/wiki/KnotTheory.

In[3]:=

K = Knot["T(3,2)"];

In[4]:=

Alexander[K][t]

KnotTheory::loading: Loading precomputed data in PD4Knots`.

Out[4]=

$t-1+t^{-1}$

In[5]:=

Conway[K][z]

Out[5]=

$z^{2}+1$

In[6]:=

Alexander[K, 2][t]

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.

Out[6]=

$\{1\}$

In[7]:=

{KnotDet[K], KnotSignature[K]}

Out[7]=

{ 3, 2 }

In[8]:=

Jones[K][q]

KnotTheory::loading: Loading precomputed data in Jones4Knots`.

Out[8]=

$-q^{4}+q^{3}+q$

In[9]:=

HOMFLYPT[K][a, z]

KnotTheory::credits: The HOMFLYPT program was written by Scott Morrison.

Out[9]=

$z^{2}a^{-2}+2a^{-2}-a^{-4}$

In[10]:=

Kauffman[K][a, z]

KnotTheory::loading: Loading precomputed data in Kauffman4Knots`.

Out[10]=

$z^{2}a^{-2}+z^{2}a^{-4}+za^{-3}+za^{-5}-2a^{-2}-a^{-4}$

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 Data:T(3,2)/V 2,1 Data:T(3,2)/V 3,1 Data:T(3,2)/V 4,1 Data:T(3,2)/V 4,2 Data:T(3,2)/V 4,3 Data:T(3,2)/V 5,1 Data:T(3,2)/V 5,2 Data:T(3,2)/V 5,3 Data:T(3,2)/V 5,4 Data:T(3,2)/V 6,1 Data:T(3,2)/V 6,2 Data:T(3,2)/V 6,3 Data:T(3,2)/V 6,4 Data:T(3,2)/V 6,5 Data:T(3,2)/V 6,6 Data:T(3,2)/V 6,7 Data:T(3,2)/V 6,8 Data:T(3,2)/V 6,9

V_2,1 through V_6,9 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 $t^{r}q^{j}$ are shown, along with their alternating sums $\chi$ (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=$2 is the signature of T(3,2). Nonzero entries off the critical diagonals (if any exist) are highlighted in red.

\   r    \    j   \	0	1	2	3	χ
9				1	-1
7					0
5			1		1
3	1				1
1	1				1

Computer Talk

Much of the above data can be recomputed by Mathematica using the package KnotTheory`. See A Sample KnotTheory` Session.

${\textrm {Include}}({\textrm {ColouredJonesM.mhtml}})$

In[1]:=	<< KnotTheory`
Loading KnotTheory` (version of August 17, 2005, 14:44:34)...
In[2]:=	Crossings[TorusKnot[3, 2]]
Out[2]=	3
In[3]:=	PD[TorusKnot[3, 2]]
Out[3]=	PD[X[3, 1, 4, 6], X[1, 5, 2, 4], X[5, 3, 6, 2]]
In[4]:=	GaussCode[TorusKnot[3, 2]]
Out[4]=	GaussCode[-2, 3, -1, 2, -3, 1]
In[5]:=	BR[TorusKnot[3, 2]]
Out[5]=	BR[2, {1, 1, 1}]
In[6]:=	alex = Alexander[TorusKnot[3, 2]][t]
Out[6]=	1 -1 + - + t t
In[7]:=	Conway[TorusKnot[3, 2]][z]
Out[7]=	2 1 + z
In[8]:=	Select[AllKnots[], (alex === Alexander[#][t])&]
Out[8]=	{Knot[3, 1]}
In[9]:=	{KnotDet[TorusKnot[3, 2]], KnotSignature[TorusKnot[3, 2]]}
Out[9]=	{3, 2}
In[10]:=	J=Jones[TorusKnot[3, 2]][q]
Out[10]=	3 4 q + q - q
In[11]:=	Select[AllKnots[], (J === Jones[#][q] || (J /. q-> 1/q) === Jones[#][q])&]
Out[11]=	{Knot[3, 1]}
In[12]:=	A2Invariant[TorusKnot[3, 2]][q]
Out[12]=	2 4 6 8 12 14 q + q + 2 q + q - q - q
In[13]:=	Kauffman[TorusKnot[3, 2]][a, z]
Out[13]=	2 2 -4 2 z z z z -a - -- + -- + -- + -- + -- 2 5 3 4 2 a a a a a
In[14]:=	{Vassiliev[2][TorusKnot[3, 2]], Vassiliev[3][TorusKnot[3, 2]]}
Out[14]=	{0, 1}
In[15]:=	Kh[TorusKnot[3, 2]][q, t]
Out[15]=	3 5 2 9 3 q + q + q t + q t