5 2

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5 1.gif

5_1

6 1.gif

6_1

5 2.gif
(KnotPlot image)

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5_2 is also known as the 3-twist knot.

The Bowstring knot of practical knot tying deforms to 5_2.


3D depiction
Simple square depiction
Lissajous curve x=cos(2t+0.2), y=cos(3t+0.7), z=cos(7t); 2 crossings can be removed

Knot presentations

Planar diagram presentation X1425 X3849 X5,10,6,1 X9,6,10,7 X7283
Gauss code -1, 5, -2, 1, -3, 4, -5, 2, -4, 3
Dowker-Thistlethwaite code 4 8 10 2 6
Conway Notation [32]


Minimum Braid Representative A Morse Link Presentation An Arc Presentation
BraidPart3.gifBraidPart3.gifBraidPart3.gifBraidPart0.gifBraidPart1.gifBraidPart0.gif
BraidPart4.gifBraidPart4.gifBraidPart4.gifBraidPart3.gifBraidPart2.gifBraidPart3.gif
BraidPart0.gifBraidPart0.gifBraidPart0.gifBraidPart4.gifBraidPart0.gifBraidPart4.gif

Length is 6, width is 3,

Braid index is 3

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

[edit Notes on presentations of 5 2]

Knot 5_2.
A graph, knot 5_2.

Three dimensional invariants

Symmetry type Reversible
Unknotting number 1
3-genus 1
Bridge index 2
Super bridge index [math]\displaystyle{ \{3,4\} }[/math]
Nakanishi index 1
Maximal Thurston-Bennequin number [-8][1]
Hyperbolic Volume 2.82812
A-Polynomial See Data:5 2/A-polynomial

[edit Notes for 5 2's three dimensional invariants]

Four dimensional invariants

Smooth 4 genus [math]\displaystyle{ 1 }[/math]
Topological 4 genus [math]\displaystyle{ 1 }[/math]
Concordance genus [math]\displaystyle{ \textrm{ConcordanceGenus}(\textrm{Knot}(5,2)) }[/math]
Rasmussen s-Invariant -2

[edit Notes for 5 2's four dimensional invariants]

Polynomial invariants

Alexander polynomial [math]\displaystyle{ 2 t+2 t^{-1} -3 }[/math]
Conway polynomial [math]\displaystyle{ 2 z^2+1 }[/math]
2nd Alexander ideal (db, data sources) [math]\displaystyle{ \{1\} }[/math]
Determinant and Signature { 7, -2 }
Jones polynomial [math]\displaystyle{ - q^{-6} + q^{-5} - q^{-4} +2 q^{-3} - q^{-2} + q^{-1} }[/math]
HOMFLY-PT polynomial (db, data sources) [math]\displaystyle{ -a^6+a^4 z^2+a^4+a^2 z^2+a^2 }[/math]
Kauffman polynomial (db, data sources) [math]\displaystyle{ a^7 z^3-2 a^7 z+a^6 z^4-2 a^6 z^2+a^6+2 a^5 z^3-2 a^5 z+a^4 z^4-a^4 z^2+a^4+a^3 z^3+a^2 z^2-a^2 }[/math]
The A2 invariant [math]\displaystyle{ -q^{20}-q^{18}+q^{12}+q^{10}+q^8+q^6+q^2 }[/math]
The G2 invariant [math]\displaystyle{ q^{100}+q^{96}-q^{94}-q^{92}+q^{90}-q^{88}-q^{84}-q^{82}-q^{78}-q^{76}-q^{74}-q^{72}-q^{68}-q^{66}+q^{64}+q^{60}+q^{56}+q^{54}+2 q^{50}-q^{48}+2 q^{46}+q^{44}+q^{40}+q^{34}+2 q^{24}+q^{20}+q^{14}+q^{10} }[/math]

"Similar" Knots (within the Atlas)

Same Alexander/Conway Polynomial: {}

Same Jones Polynomial (up to mirroring, [math]\displaystyle{ q\leftrightarrow q^{-1} }[/math]): {K11n57,}

Vassiliev invariants

V2 and V3: (2, -3)
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
[math]\displaystyle{ 8 }[/math] [math]\displaystyle{ -24 }[/math] [math]\displaystyle{ 32 }[/math] [math]\displaystyle{ \frac{268}{3} }[/math] [math]\displaystyle{ \frac{44}{3} }[/math] [math]\displaystyle{ -192 }[/math] [math]\displaystyle{ -368 }[/math] [math]\displaystyle{ -64 }[/math] [math]\displaystyle{ -56 }[/math] [math]\displaystyle{ \frac{256}{3} }[/math] [math]\displaystyle{ 288 }[/math] [math]\displaystyle{ \frac{2144}{3} }[/math] [math]\displaystyle{ \frac{352}{3} }[/math] [math]\displaystyle{ \frac{22951}{15} }[/math] [math]\displaystyle{ -\frac{28}{5} }[/math] [math]\displaystyle{ \frac{29764}{45} }[/math] [math]\displaystyle{ \frac{137}{9} }[/math] [math]\displaystyle{ \frac{1351}{15} }[/math]

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 [math]\displaystyle{ t^rq^j }[/math] are shown, along with their alternating sums [math]\displaystyle{ \chi }[/math] (fixed [math]\displaystyle{ j }[/math], alternation over [math]\displaystyle{ r }[/math]). The squares with yellow highlighting are those on the "critical diagonals", where [math]\displaystyle{ j-2r=s+1 }[/math] or [math]\displaystyle{ j-2r=s-1 }[/math], where [math]\displaystyle{ s= }[/math]-2 is the signature of 5 2. Nonzero entries off the critical diagonals (if any exist) are highlighted in red.   
\ r
  \  
j \
-5-4-3-2-10χ
-1     11
-3    110
-5   1  1
-7   1  1
-9 11   0
-11      0
-131     -1
Integral Khovanov Homology

(db, data source)

  
[math]\displaystyle{ \dim{\mathcal G}_{2r+i}\operatorname{KH}^r_{\mathbb Z} }[/math] [math]\displaystyle{ i=-3 }[/math] [math]\displaystyle{ i=-1 }[/math]
[math]\displaystyle{ r=-5 }[/math] [math]\displaystyle{ {\mathbb Z} }[/math]
[math]\displaystyle{ r=-4 }[/math] [math]\displaystyle{ {\mathbb Z}_2 }[/math] [math]\displaystyle{ {\mathbb Z} }[/math]
[math]\displaystyle{ r=-3 }[/math] [math]\displaystyle{ {\mathbb Z} }[/math]
[math]\displaystyle{ r=-2 }[/math] [math]\displaystyle{ {\mathbb Z}\oplus{\mathbb Z}_2 }[/math] [math]\displaystyle{ {\mathbb Z} }[/math]
[math]\displaystyle{ r=-1 }[/math] [math]\displaystyle{ {\mathbb Z}_2 }[/math] [math]\displaystyle{ {\mathbb Z} }[/math]
[math]\displaystyle{ r=0 }[/math] [math]\displaystyle{ {\mathbb Z} }[/math] [math]\displaystyle{ {\mathbb Z} }[/math]

The Coloured Jones Polynomials