7 4
|  |  | 
|  (KnotPlot image) | See the full Rolfsen Knot Table. Visit 7 4's page at the Knot Server (KnotPlot driven, includes 3D interactive images!) | 
| Simplest version of Endless knot symbol. | 
|   a knot seen at the Castle of Kornik [3] |   A 7-4 knot reduced from TakaraMusubi with 9 crossings [4] |   TakaraMusubi knot seen in Japanese symbols, or Kolam in South India [5] | |
|   A laser cut by Tom Longtin [6] | |||
| 
 | 
Knot presentations
| Planar diagram presentation | X6271 X12,6,13,5 X14,8,1,7 X8,14,9,13 X2,12,3,11 X10,4,11,3 X4,10,5,9 | 
| Gauss code | 1, -5, 6, -7, 2, -1, 3, -4, 7, -6, 5, -2, 4, -3 | 
| Dowker-Thistlethwaite code | 6 10 12 14 4 2 8 | 
| Conway Notation | [313] | 
| Minimum Braid Representative | A Morse Link Presentation | An Arc Presentation | ||||
| 
 Length is 9, width is 4, Braid index is 4 |   |  [{3, 5}, {6, 4}, {5, 7}, {2, 6}, {8, 3}, {7, 9}, {1, 8}, {9, 2}, {4, 1}] | 
[edit Notes on presentations of 7 4]
KnotTheory`. Your input (in red) is realistic; all else should have the same content as in a real mathematica session, but with different formatting.
(The path below may be different on your system, and possibly also the KnotTheory` date)
| In[1]:= | AppendTo[$Path, "C:/drorbn/projects/KAtlas/"];
<< KnotTheory` | 
| Loading KnotTheory` version of May 31, 2006, 14:15:20.091.
 | 
| In[3]:= | K = Knot["7 4"]; | 
| In[4]:= | PD[K] | 
| KnotTheory::loading: Loading precomputed data in PD4Knots`. | 
| Out[4]= | X6271 X12,6,13,5 X14,8,1,7 X8,14,9,13 X2,12,3,11 X10,4,11,3 X4,10,5,9 | 
| In[5]:= | GaussCode[K] | 
| Out[5]= | 1, -5, 6, -7, 2, -1, 3, -4, 7, -6, 5, -2, 4, -3 | 
| In[6]:= | DTCode[K] | 
| Out[6]= | 6 10 12 14 4 2 8 | 
(The path below may be different on your system)
| In[7]:= | AppendTo[$Path, "C:/bin/LinKnot/"]; | 
| In[8]:= | ConwayNotation[K] | 
| Out[8]= | [313] | 
| In[9]:= | br = BR[K] | 
| KnotTheory::credits: The minimum braids representing the knots with up to 10 crossings were provided by Thomas Gittings. See arXiv:math.GT/0401051. | 
| Out[9]= | 
| In[10]:= | {First[br], Crossings[br], BraidIndex[K]} | 
| KnotTheory::credits: The braid index data known to KnotTheory` is taken from Charles Livingston's http://www.indiana.edu/~knotinfo/. | 
| KnotTheory::loading: Loading precomputed data in IndianaData`. | 
| Out[10]= | { 4, 9, 4 } | 
| In[11]:= | Show[BraidPlot[br]] | 
| 
 | 
| Out[11]= | -Graphics- | 
| In[12]:= | Show[DrawMorseLink[K]] | 
| KnotTheory::credits: "MorseLink was added to KnotTheory` by Siddarth Sankaran at the University of Toronto in the summer of 2005." | 
| KnotTheory::credits: "DrawMorseLink was written by Siddarth Sankaran at the University of Toronto in the summer of 2005." | 
|   | 
| Out[12]= | -Graphics- | 
| In[13]:= | ap = ArcPresentation[K] | 
| Out[13]= | ArcPresentation[{3, 5}, {6, 4}, {5, 7}, {2, 6}, {8, 3}, {7, 9}, {1, 8}, {9, 2}, {4, 1}] | 
| In[14]:= | Draw[ap] | 
|   | 
| Out[14]= | -Graphics- | 
Three dimensional invariants
| 
 | 
Four dimensional invariants
| 
 | 
Polynomial invariants
A1 Invariants.
| Weight | Invariant | 
|---|---|
| 1 | |
| 2 | |
| 3 | |
| 4 | |
| 5 | |
| 6 | 
A2 Invariants.
| Weight | Invariant | 
|---|---|
| 1,0 | |
| 1,1 | |
| 2,0 | |
| 3,0 | 
A3 Invariants.
| Weight | Invariant | 
|---|---|
| 0,1,0 | |
| 1,0,0 | 
A4 Invariants.
| Weight | Invariant | 
|---|---|
| 0,1,0,0 | |
| 1,0,0,0 | 
B2 Invariants.
| Weight | Invariant | 
|---|---|
| 0,1 | |
| 1,0 | 
D4 Invariants.
| Weight | Invariant | 
|---|---|
| 1,0,0,0 | 
G2 Invariants.
| Weight | Invariant | 
|---|---|
| 1,0 | 
.
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[$Path, "C:/drorbn/projects/KAtlas/"];
<< KnotTheory` | 
| Loading KnotTheory` version of August 31, 2006, 11:25:27.5625.
 | 
| In[3]:= | K = Knot["7 4"]; | 
| In[4]:= | Alexander[K][t] | 
| KnotTheory::loading: Loading precomputed data in PD4Knots`. | 
| Out[4]= | 
| In[5]:= | Conway[K][z] | 
| Out[5]= | 
| In[6]:= | Alexander[K, 2][t] | 
| KnotTheory::credits: The program Alexander[K, r] to compute Alexander ideals was written by Jana Archibald at the University of Toronto in the summer of 2005. | 
| Out[6]= | 
| In[7]:= | {KnotDet[K], KnotSignature[K]} | 
| Out[7]= | { 15, 2 } | 
| In[8]:= | Jones[K][q] | 
| KnotTheory::loading: Loading precomputed data in Jones4Knots`. | 
| Out[8]= | 
| In[9]:= | HOMFLYPT[K][a, z] | 
| KnotTheory::credits: The HOMFLYPT program was written by Scott Morrison. | 
| Out[9]= | 
| In[10]:= | Kauffman[K][a, z] | 
| KnotTheory::loading: Loading precomputed data in Kauffman4Knots`. | 
| Out[10]= | 
"Similar" Knots (within the Atlas)
Same Alexander/Conway Polynomial: {9_2,}
Same Jones Polynomial (up to mirroring, ): {}
KnotTheory`. Your input (in red) is realistic; all else should have the same content as in a real mathematica session, but with different formatting.
(The path below may be different on your system, and possibly also the KnotTheory` date)
| In[1]:= | AppendTo[$Path, "C:/drorbn/projects/KAtlas/"];
<< KnotTheory` | 
| Loading KnotTheory` version of May 31, 2006, 14:15:20.091.
 | 
| In[3]:= | K = Knot["7 4"]; | 
| In[4]:= | {A = Alexander[K][t], J = Jones[K][q]} | 
| KnotTheory::loading: Loading precomputed data in PD4Knots`. | 
| KnotTheory::loading: Loading precomputed data in Jones4Knots`. | 
| Out[4]= | { , } | 
| In[5]:= | DeleteCases[Select[AllKnots[], (A === Alexander[#][t]) &], K] | 
| KnotTheory::loading: Loading precomputed data in DTCode4KnotsTo11`. | 
| KnotTheory::credits: The GaussCode to PD conversion was written by Siddarth Sankaran at the University of Toronto in the summer of 2005. | 
| Out[5]= | {9_2,} | 
| In[6]:= | DeleteCases[
  Select[
    AllKnots[],
    (J === Jones[#][q] || (J /. q -> 1/q) === Jones[#][q]) &
    ],
  K
  ] | 
| KnotTheory::loading: Loading precomputed data in Jones4Knots11`. | 
| Out[6]= | {} | 
Vassiliev invariants
| V2 and V3: | (4, 8) | 
| V2,1 through 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 4. Nonzero entries off the critical diagonals (if any exist) are highlighted in red. | 
 | 
| Integral Khovanov Homology (db, data source) |  | 
The Coloured Jones Polynomials
| 2 | |
| 3 | |
| 4 | |
| 5 | |
| 6 | |
| 7 | 
Computer Talk
Much of the above data can be recomputed by Mathematica using the package KnotTheory`. See A Sample KnotTheory` Session, or any of the Computer Talk sections above.
Modifying This Page
| Read me first: Modifying Knot Pages See/edit the Rolfsen Knot Page master template (intermediate). See/edit the Rolfsen_Splice_Base (expert). Back to the top. | 
 | 




















