8 2

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8_1

8_3

Contents

Image:8 2.gif
(KnotPlot image)

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[edit] Knot presentations

Planar diagram presentation X1425 X5,12,6,13 X3,11,4,10 X11,3,12,2 X7,14,8,15 X9,16,10,1 X13,6,14,7 X15,8,16,9
Gauss code -1, 4, -3, 1, -2, 7, -5, 8, -6, 3, -4, 2, -7, 5, -8, 6
Dowker-Thistlethwaite code 4 10 12 14 16 2 6 8
Conway Notation [512]


Minimum Braid Representative A Morse Link Presentation An Arc Presentation
Image:BraidPart3.gifImage:BraidPart3.gifImage:BraidPart3.gifImage:BraidPart3.gifImage:BraidPart3.gifImage:BraidPart0.gifImage:BraidPart3.gifImage:BraidPart0.gif
Image:BraidPart4.gifImage:BraidPart4.gifImage:BraidPart4.gifImage:BraidPart4.gifImage:BraidPart4.gifImage:BraidPart1.gifImage:BraidPart4.gifImage:BraidPart1.gif
Image:BraidPart0.gifImage:BraidPart0.gifImage:BraidPart0.gifImage:BraidPart0.gifImage:BraidPart0.gifImage:BraidPart2.gifImage:BraidPart0.gifImage:BraidPart2.gif

Length is 8, width is 3,

Braid index is 3

Image:8 2_ML.gif Image:8 2_AP.gif
[{10, 2}, {1, 8}, {9, 3}, {2, 4}, {8, 10}, {3, 5}, {4, 6}, {5, 7}, {6, 9}, {7, 1}]

[edit Notes on presentations of 8 2]

Knot 8_2.
Knot 8_2.
A graph, knot 8_2.
A graph, knot 8_2.

[edit] Three dimensional invariants

Symmetry type Reversible
Unknotting number 2
3-genus 3
Bridge index 2
Super bridge index {4,5}
Nakanishi index 1
Maximal Thurston-Bennequin number [-11][1]
Hyperbolic Volume 4.93524
A-Polynomial See Data:8 2/A-polynomial

[edit Notes for 8 2's three dimensional invariants]

[edit] Four dimensional invariants

Smooth 4 genus 2
Topological 4 genus 2
Concordance genus 3
Rasmussen s-Invariant -4

[edit Notes for 8 2's four dimensional invariants]

[edit] Polynomial invariants

Alexander polynomial t3 + 3t2−3t + 3−3t−1 + 3t−2t−3
Conway polynomial z6−3z4 + 1
2nd Alexander ideal (db, data sources) {1}
Determinant and Signature { 17, -4 }
Jones polynomial 1−q−1 + 2q−2−2q−3 + 3q−4−3q−5 + 2q−6−2q−7 + q−8
HOMFLY-PT polynomial (db, data sources) z4a6 + 3z2a6 + a6z6a4−5z4a4−7z2a4−3a4 + z4a2 + 4z2a2 + 3a2
Kauffman polynomial (db, data sources) z2a10 + 2z3a9za9 + 2z4a8z2a8 + 2z5a7−2z3a7za7 + 2z6a6−5z4a6 + 3z2a6a6 + z7a5−2z5a5z3a5 + za5 + 3z6a4−12z4a4 + 12z2a4−3a4 + z7a3−4z5a3 + 3z3a3 + za3 + z6a2−5z4a2 + 7z2a2−3a2
The A2 invariant q24q18q16q12 + q10 + q6 + q4 + q2 + 1
The G2 invariant q134q132 + q130q128q126q122 + 2q120−2q118 + q116 + q110 + q106q104 + q102 + q96 + 2q92q84 + q82−2q78 + q76q74 + q70−4q68 + 2q66−3q64−3q58 + 3q56−2q54 + q52q50q48 + q46−2q44 + q42q38 + q36 + q32 + 2q30−2q28 + 3q26q24 + q22 + 3q20−3q18 + 4q16 + q12 + q10q8 + 2q6 + q2

[edit] "Similar" Knots (within the Atlas)

Same Alexander/Conway Polynomial: {K11n6,}

Same Jones Polynomial (up to mirroring, q\leftrightarrow q^{-1}): {}

[edit] Vassiliev invariants

V2 and V3: (0, 1)

[edit] 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 = -4 is the signature of 8 2. Nonzero entries off the critical diagonals (if any exist) are highlighted in red.   
\ r
  \  
j \
-6-5-4-3-2-1012χ
1        11
-1         0
-3      21 1
-5     11  0
-7    21   1
-9   11    0
-11  12     -1
-13 11      0
-15 1       -1
-171        1
Integral Khovanov Homology

(db, data source)

  
\dim{\mathcal G}_{2r+i}\operatorname{KH}^r_{\mathbb Z} i = −5 i = −3
r = −6 {\mathbb Z}
r = −5 {\mathbb Z}\oplus{\mathbb Z}_2 {\mathbb Z}
r = −4 {\mathbb Z}\oplus{\mathbb Z}_2 {\mathbb Z}
r = −3 {\mathbb Z}^{2}\oplus{\mathbb Z}_2 {\mathbb Z}
r = −2 {\mathbb Z}\oplus{\mathbb Z}_2^{2} {\mathbb Z}^{2}
r = −1 {\mathbb Z}\oplus{\mathbb Z}_2 {\mathbb Z}
r = 0 {\mathbb Z}\oplus{\mathbb Z}_2 {\mathbb Z}^{2}
r = 1 {\mathbb Z}
r = 2 {\mathbb Z}_2 {\mathbb Z}

[edit] The Coloured Jones Polynomials

[edit] 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.

[edit] 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).

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