9 1

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8 21.gif

8_21

9 2.gif

9_2

9 1.gif
(KnotPlot image)

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9_1 should perhaps be called "The Nonafoil Knot", following the trefoil knot, the cinquefoil knot and (maybe) the septafoil knot. The next in the series is K11a367. See also T(9,2).


Interlaced form of 9/2 star polygon or "nonagram"
Decorative interlaced form of 9/2 star polygon or "nonagram"
Alternate interlaced form of 9/2 star polygon or "nonagram"

Knot presentations

Planar diagram presentation X1,10,2,11 X3,12,4,13 X5,14,6,15 X7,16,8,17 X9,18,10,1 X11,2,12,3 X13,4,14,5 X15,6,16,7 X17,8,18,9
Gauss code -1, 6, -2, 7, -3, 8, -4, 9, -5, 1, -6, 2, -7, 3, -8, 4, -9, 5
Dowker-Thistlethwaite code 10 12 14 16 18 2 4 6 8
Conway Notation [9]


Minimum Braid Representative A Morse Link Presentation An Arc Presentation
BraidPart3.gifBraidPart3.gifBraidPart3.gifBraidPart3.gifBraidPart3.gifBraidPart3.gifBraidPart3.gifBraidPart3.gifBraidPart3.gif
BraidPart4.gifBraidPart4.gifBraidPart4.gifBraidPart4.gifBraidPart4.gifBraidPart4.gifBraidPart4.gifBraidPart4.gifBraidPart4.gif

Length is 9, width is 2,

Braid index is 2

9 1 ML.gif 9 1 AP.gif
[{11, 2}, {1, 3}, {2, 4}, {3, 5}, {4, 6}, {5, 7}, {6, 8}, {7, 9}, {8, 10}, {9, 11}, {10, 1}]

[edit Notes on presentations of 9 1]


Three dimensional invariants

Symmetry type Reversible
Unknotting number 4
3-genus 4
Bridge index 2
Super bridge index 4
Nakanishi index 1
Maximal Thurston-Bennequin number [-18][7]
Hyperbolic Volume Not hyperbolic
A-Polynomial See Data:9 1/A-polynomial

[edit Notes for 9 1's three dimensional invariants]

Four dimensional invariants

Smooth 4 genus
Topological 4 genus
Concordance genus
Rasmussen s-Invariant -8

[edit Notes for 9 1's four dimensional invariants]

Polynomial invariants

Alexander polynomial
Conway polynomial
2nd Alexander ideal (db, data sources)
Determinant and Signature { 9, -8 }
Jones polynomial
HOMFLY-PT polynomial (db, data sources)
Kauffman polynomial (db, data sources)
The A2 invariant
The G2 invariant

"Similar" Knots (within the Atlas)

Same Alexander/Conway Polynomial: {}

Same Jones Polynomial (up to mirroring, ): {}

Vassiliev invariants

V2 and V3: (10, -30)
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 -8 is the signature of 9 1. Nonzero entries off the critical diagonals (if any exist) are highlighted in red.   
\ r
  \  
j \
-9-8-7-6-5-4-3-2-10χ
-7         11
-9         11
-11       1  1
-13          0
-15     11   0
-17          0
-19   11     0
-21          0
-23 11       0
-25          0
-271         -1
Integral Khovanov Homology

(db, data source)

  

The Coloured Jones Polynomials