List of prime knots

Last updated

In knot theory, prime knots are those knots that are indecomposable under the operation of knot sum. The prime knots with ten or fewer crossings are listed here for quick comparison of their properties and varied naming schemes.

Contents

Table of prime knots

Six or fewer crossings

NamePicture Alexander–
Briggs

Rolfsen
Dowker–
Thistlethwaite
Dowker
notation
Conway
notation
crossinglist
Unknot Blue Unknot.png 010a10
Trefoil knot Blue Trefoil Knot.png 313a14 6 2[3]123:123
Figure-eight knot Blue Figure-Eight Knot.png 414a14 6 8 2[22]1234:2143

1231\4324

Cinquefoil knot Blue Cinquefoil Knot.png 515a26 8 10 2 4[5]12345:12345
Three-twist knot Blue Three-Twist Knot.png 525a14 8 10 2 6[32]12345:12543

1231\452354

Stevedore knot Blue Stevedore Knot.png 616a34 8 12 10 2 6[42]123456:216543

1231\45632654

62 knot Blue 6 2 Knot.png 626a24 8 10 12 2 6[312]123456:234165

1231\45632456

63 knot Blue 6 3 Knot.png 636a14 8 10 2 12 6[2112]123456:236145

1231\45642356

1231\45236456

Seven crossings

PictureAlexander–
Briggs–
Rolfsen
Dowker–
Thistlethwaite
Dowker
notation
Conway
notation
crossinglist
Blue 7 1 Knot.png 71 7a78 10 12 14 2 4 6[7]1-7:1-7
Blue 7 2 Knot.png 72 7a44 10 14 12 2 8 6[52]1-7:127-3
7-3 knot.svg 737a56 10 12 14 2 4 8[43]
Celtic-knot-linear-7crossings.svg 74 7a66 10 12 14 4 2 8[313]
7-5 knot.svg 757a34 10 12 14 2 8 6[322]
7-6 knot.svg 767a24 8 12 2 14 6 10[2212]
7-7 knot.svg 777a14 8 10 12 2 14 6[21112]

Eight crossings

PictureAlexander–
Briggs–
Rolfsen
Dowker–
Thistlethwaite
Dowker
notation
Conway
notation
Blue 8 1 Knot.png 81 8a­114 10 16 14 12 2 8 6[62]
Knot-8-2.png 828a84 10 12 14 16 2 6 8[512]
Knot 8 3.svg 838a­186 12 10 16 14 4 2 8[44]
8-4 Knot.svg 848a­176 10 12 16 14 4 2 8[413]
Knot8-5.png 858a­136 8 12 2 14 16 4 10[3,3,2]
8-6 knot.svg 868a­104 10 14 16 12 2 8 6[332]

Knot87.png

878a64 10 12 14 2 16 6 8[4112]

Knot88.png

888a44 8 12 2 16 14 6 10[2312]

Knot89.png

898a­166 10 12 14 16 4 2 8[3113]

Knot810.png

8108a34 8 12 2 14 16 6 10[3,21,2]

Knot811.png

8118a94 10 12 14 16 2 8 6[3212]
8crossings-rose-limacon-knot.svg 8128a54 8 14 10 2 16 6 12[2222]

Knot813.png

8138a74 10 12 14 2 16 8 6[31112]

Knot814.png

8148a14 8 10 14 2 16 6 12[22112]
8crossings-two-trefoils.svg 8158a24 8 12 2 14 6 16 10[21,21,2]
8-16 knot.svg 8168a­156 8 14 12 4 16 2 10[.2.20]
8 17 Knot.svg 8178a­146 8 12 14 4 16 2 10[.2.2]
8crossing-symmetrical.svg 818 8a­126 8 10 12 14 16 2 4[8*]
8crossing-symmetrical-nonalternating.svg 819 8n34 8 -12 2 -14 -16 -6 -10[3,3,2-]
Knot 8 20.svg 8208n14 8 -12 2 -14 -6 -16 -10[3,21,2-]
Lissajous 8 21 Knot.png 8218n24 8 -12 2 14 -6 16 10[21,21,2-]

Nine crossings

PictureAlexander–
Briggs–
Rolfsen
Dowker–
Thistlethwaite
Dowker
notation
Conway
notation
9-2 star polygon interlaced.svg 91 9a­4110 12 14 16 18 2 4 6 8[9]
Knot92.png 92 9a­274 12 18 16 14 2 10 8 6[72]
Knot93.png 939a­388 12 14 16 18 2 4 6 10[63]
Knot94.png 949a­356 12 14 18 16 2 4 10 8[54]

Knot95.png

959a­366 12 14 18 16 4 2 10 8[513]

Knot96.png

969a­234 12 14 16 18 2 10 6 8[522]

Knot97.png

979a­264 12 16 18 14 2 10 8 6[342]

Knot98.png

989a84 8 14 2 18 16 6 12 10[2412]

Knot99.png

999a­336 12 14 16 18 2 4 10 8[423]

Knot910.png

9109a­398 12 14 16 18 2 6 4 10[333]

Knot911.png

9119a­204 10 14 16 12 2 18 6 8[4122]
Knot912.png 9129a­224 10 16 14 2 18 8 6 12[4212]
Knot913.png 9139a­346 12 14 16 18 4 2 10 8[3213]
Knot914.png 9149a­174 10 12 16 14 2 18 8 6[41112]
Knot915.png 9159a­104 8 14 10 2 18 16 6 12[2322]
Knot916.png 9169a­254 12 16 18 14 2 8 10 6[3,3,2+]
Knot917.png 9179a­144 10 12 14 16 2 6 18 8[21312]
Knot918.png 9189a­244 12 14 16 18 2 10 8 6[3222]
Knot919.png 9199a34 8 10 14 2 18 16 6 12[23112]

Knot920.png

9209a­194 10 14 16 2 18 8 6 12[31212]

Knot921.png

9219a­214 10 14 16 12 2 18 8 6[31122]

Knot922.png

9229a24 8 10 14 2 16 18 6 12[211,3,2]
9crossing-knot symmetrical grid.svg 9239a­164 10 12 16 2 8 18 6 14[22122]

Knot924.png

9249a74 8 14 2 16 18 6 12 10[3,21,2+]

Knot925.png

9259a44 8 12 2 16 6 18 10 14[22,21,2]

Knot926.png

9269a­154 10 12 14 16 2 18 8 6[311112]

Knot927.png

9279a­124 10 12 14 2 18 16 6 8[212112]

Knot928.png

9289a54 8 12 2 16 14 6 18 10[21,21,2+]

Knot929.png

9299a­316 10 14 18 4 16 8 2 12[.2.20.2]

Knot930.png

9309a14 8 10 14 2 16 6 18 12[211,21,2]

Knot931.png

9319a­134 10 12 14 2 18 16 8 6[2111112]

Knot932.png

9329a64 8 12 14 2 16 18 10 6[.21.20]

Knot933.png

9339a­114 8 14 12 2 16 18 10 6[.21.2]

Knot934.png

9349a­286 8 10 16 14 18 4 2 12[8*20]
9crossings-threesymmetric-other.svg 9359a­408 12 16 14 18 4 2 6 10[3,3,3]

Knot936.png

9369a94 8 14 10 2 16 18 6 12[22,3,2]

Knot937.png

9379a­184 10 14 12 16 2 6 18 8[3,21,21]

Knot938.png

9389a­306 10 14 18 4 16 2 8 12[.2.2.2]

Knot939.png

9399a­326 10 14 18 16 2 8 4 12[2:2:20]
Knot-9crossings-symmetrical.svg 9409a­276 16 14 12 4 2 18 10 8[9*]
9crossings-decorative-knot-threefold-incircle.svg 9419a­296 10 14 12 16 2 18 4 8[20:20:20]

Knot942.png

9429n44 8 10 14 2 16 18 6 12[22,3,2]

Knot943.png

9439n34 8 10 14 2 16 6 18 12[211,3,2]

Knot944.png

9449n14 8 10 14 2 16 6 18 12[22,21,2]

Knot945.png

9459n24 8 10 14 2 16 6 18 12[211,21,2]

Knot946.png

9469n54 10 14 12 16 2 6 18 8[3,3,21]
9-crossing non-alternating 3-symmetrical.svg 9479n76 8 10 16 14 18 4 2 12[8*-20]

Knot948.png

9489n64 10 14 12 16 2 6 18 8[21,21,21]

Knot949.png

9499n86 -10 14 12 16 2 18 4 8[20:20:20]

Ten crossings

PictureAlexander–
Briggs–
Rolfsen
Dowker–
Thistlethwaite
Dowker
notation
Conway
notation
101 10a­754 12 20 18 16 14 2 10 8 6[82]
10210a­594 12 14 16 18 20 2 6 8 10[712]
10310a­­1176 14 12 20 18 16 4 2 10 8[64]
10410a­­1136 12 14 20 18 16 4 2 10 8[613]
10510a­564 12 14 16 18 2 20 6 8 10[6112]
10610a­704 12 16 18 20 14 2 10 6 8[532]
10710a­654 12 14 18 16 20 2 10 8 6[5212]
10810a­­1146 14 12 16 18 20 4 2 8 10[514]
10910a­­1106 12 14 16 18 20 4 2 8 10[5113]
101010a­644 12 14 18 16 2 20 10 8 6[51112]
101110a­­1166 14 12 18 20 16 4 2 10 8[433]
101210a­434 10 14 16 2 20 18 6 8 12[4312]
101310a­544 10 18 16 12 2 20 8 6 14[4222]
101410a­334 10 12 16 18 2 20 6 8 14[42112]
101510a­684 12 16 18 14 2 10 20 6 8[4132]
101610a­­1156 14 12 16 18 20 4 2 10 8[4123]
101710a­­1076 12 14 16 18 2 4 20 8 10[4114]
101810a­634 12 14 18 16 2 10 20 8 6[41122]
101910a­­1086 12 14 16 18 2 4 20 10 8[41113]
102010a­744 12 18 20 16 14 2 10 8 6[352]
102110a­604 12 14 16 18 20 2 6 10 8[3412]
102210a­­1126 12 14 18 20 16 4 2 10 8[3313]
102310a­574 12 14 16 18 2 20 6 10 8[33112]
102410a­714 12 16 18 20 14 2 10 8 6[3232]
Knot-10-25-sm.png 102510a­614 12 14 16 18 20 2 10 8 6[32212]
102610a­­1116 12 14 16 18 20 4 2 10 8[32113]
102710a­584 12 14 16 18 2 20 10 8 6[321112]
102810a­444 10 14 16 2 20 18 8 6 12[31312]
102910a­534 10 16 18 12 2 20 8 6 14[31222]
103010a­344 10 12 16 18 2 20 8 6 14[312112]
103110a­694 12 16 18 14 2 10 20 8 6[31132]
103210a­554 12 14 16 18 2 10 20 8 6[311122]
103310a­­1096 12 14 16 18 4 2 20 10 8[311113]
103410a­194 8 14 2 20 18 16 6 12 10[2512]
103510a­234 8 16 10 2 20 18 6 14 12[2422]
103610a54 8 10 16 2 20 18 6 14 12[24112]
103710a­494 10 16 12 2 8 20 18 6 14[2332]
103810a­294 10 12 16 2 8 20 18 6 14[23122]
103910a­264 10 12 14 18 2 6 20 8 16[22312]
104010a­304 10 12 16 2 20 6 18 8 14[222112]
104110a­354 10 12 16 20 2 8 18 6 14[221212]
104210a­314 10 12 16 2 20 8 18 6 14[2211112]
104310a­524 10 16 14 2 20 8 18 6 12[212212]
104410a­324 10 12 16 14 2 20 18 8 6[2121112]
104510a­254 10 12 14 16 2 20 18 8 6[21111112]
104610a­816 8 14 2 16 18 20 4 10 12[5,3,2]
104710a­154 8 14 2 16 18 20 6 10 12[5,21,2]
104810a­796 8 14 2 16 18 4 20 10 12[41,3,2]
104910a­134 8 14 2 16 18 6 20 10 12[41,21,2]
105010a­826 8 14 2 16 18 20 4 12 10[32,3,2]
105110a­164 8 14 2 16 18 20 6 12 10[32,21,2]
105210a­806 8 14 2 16 18 4 20 12 10[311,3,2]
105310a­144 8 14 2 16 18 6 20 12 10[311,21,2]
105410a­484 10 16 12 2 8 18 20 6 14[23,3,2]
105510a94 8 12 2 16 6 20 18 10 14[23,21,2]
105610a­284 10 12 16 2 8 18 20 6 14[221,3,2]
105710a64 8 12 2 14 18 6 20 10 16[221,21,2]
105810a­204 8 14 10 2 18 6 20 12 16[22,22,2]
10-59 knot theory square.svg 105910a24 8 10 14 2 18 6 20 12 16[22,211,2]
10-60 knot theory square.svg 106010a14 8 10 14 2 16 18 6 20 12[211,211,2]
106110a­­1238 10 16 14 2 18 20 6 4 12[4,3,3]
106210a­414 10 14 16 2 18 20 6 8 12[4,3,21]
106310a­514 10 16 14 2 18 8 6 20 12[4,21,21]
106410a­­1228 10 14 16 2 18 20 6 4 12[31,3,3]
106510a­424 10 14 16 2 18 20 8 6 12[31,3,21]
106610a­404 10 14 16 2 18 8 6 20 12[31,21,21]
106710a­374 10 14 12 18 2 6 20 8 16[22,3,21]
106810a­674 12 16 14 18 2 20 6 10 8[211,3,3]
106910a­384 10 14 12 18 2 16 6 20 8[211,21,21]
107010a­224 8 16 10 2 18 20 6 14 12[22,3,2+]
107110a­104 8 12 2 18 14 6 20 10 16[22,21,2+]
107210a44 8 10 16 2 18 20 6 14 12[211,3,2+]
107310a34 8 10 14 2 18 16 6 20 12[211,21,2+]
107410a­624 12 14 16 20 18 2 8 6 10[3,3,21+]
Vodicka knot modified.svg 107510a­274 10 12 14 18 2 16 6 20 8[21,21,21+]
107610a­734 12 18 20 14 16 2 10 8 6[3,3,2++]
107710a­184 8 14 2 18 20 16 6 12 10[3,21,2++]
107810a­174 8 14 2 18 16 6 12 20 10[21,21,2++]
107910a­786 8 12 2 16 4 18 20 10 14[(3,2)(3,2)]
108010a84 8 12 2 16 6 18 20 10 14[(3,2)(21,2)]
108110a74 8 12 2 16 6 18 10 20 14[(21,2)(21,2)]
108210a­836 8 14 16 4 18 20 2 10 12[.4.2]
108310a­846 8 16 14 4 18 20 2 12 10[.31.20]
108410a­504 10 16 14 2 8 18 20 12 6[.22.2]
108510a­866 8 16 14 4 18 20 2 10 12[.4.20]
108610a­876 8 14 16 4 18 20 2 12 10[.31.2]
108710a­394 10 14 16 2 8 18 20 12 6[.22.20]
108810a­114 8 12 14 2 16 20 18 10 6[.21.21]
108910a­214 8 14 12 2 16 20 18 10 6[.21.210]
109010a­926 10 14 2 16 20 18 8 4 12[.3.2.2]
109110a­­1066 10 20 14 16 18 4 8 2 12[.3.2.20]
109210a­464 10 14 18 2 16 8 20 12 6[.21.2.20]
109310a­­1016 10 16 20 14 4 18 2 12 8[.3.20.2]
109410a­916 10 14 2 16 18 20 8 4 12[.30.2.2]
109510a­474 10 14 18 2 16 20 8 12 6[.210.2.2]
109610a­244 8 18 12 2 16 20 6 10 14[.2.21.2]
109710a­124 8 12 18 2 16 20 6 10 14[.2.210.2]
109810a­966 10 14 18 2 16 20 4 8 12[.2.2.2.20]
109910a­­1036 10 18 14 2 16 20 8 4 12[.2.2.20.20]
1010010a­­1046 10 18 14 16 4 20 8 2 12[3:2:2]
1010110a­454 10 14 18 2 16 6 20 8 12[21:2:2]
1010210a­976 10 14 18 16 4 20 2 8 12[3:2:20]
1010310a­­1056 10 18 16 14 4 20 8 2 12[30:2:2]
1010410a­­1186 16 12 14 18 4 20 2 8 10[3:20:20]
1010510a­724 12 16 20 18 2 8 6 10 14[21:20:20]
1010610a­956 10 14 16 18 4 20 2 8 12[30:2:20]
1010710a­664 12 16 14 18 2 8 20 10 6[210:2:20]
1010810a­­1196 16 12 14 18 4 20 2 10 8[30:20:20]
1010910a­936 10 14 16 2 18 4 20 8 12[2.2.2.2]
1011010a­­1006 10 16 20 14 2 18 4 8 12[2.2.2.20]
1011110a­986 10 16 14 2 18 8 20 4 12[2.2.20.2]
1011210a­766 8 10 14 16 18 20 2 4 12[8*3]
1011310a­364 10 14 12 2 16 18 20 8 6[8*21]
1011410a­776 8 10 14 16 20 18 2 4 12[8*30]
1011510a­946 10 14 16 4 18 2 20 12 8[8*20.20]
Triquetra-heart-knot.svg 1011610a­­1206 16 18 14 2 4 20 8 10 12[8*2:2]
1011710a­996 10 16 14 18 4 20 2 12 8[8*2:20]
1011810a­886 8 18 14 16 4 20 2 10 12[8*2:.2]
1011910a­856 8 14 18 16 4 20 10 2 12[8*2:.20]
Two-trefoils-on-loop doubly-interlinked 10crossings.svg 1012010a­­1026 10 18 12 4 16 20 8 2 14[8*20::20]
1012110a­906 10 12 20 18 16 8 2 4 14[9*20]
10crossings-two-triquetras-joined.svg 1012210a­896 10 12 14 18 16 20 2 4 8[9*.20]
Floral fivefold knot green (geometry).svg 1012310a­­1218 10 12 14 16 18 20 2 4 6[10*]
10124 10n­214 8 -14 2 -16 -18 -20 -6 -10 -12[5,3,2-]
1012510n­154 8 14 2 -16 -18 6 -20 -10 -12[5,21,2-]
1012610n­174 8 -14 2 -16 -18 -6 -20 -10 -12[41,3,2-]
1012710n­164 8 -14 2 16 18 -6 20 10 12[41,21,2-]
1012810n­224 8 -14 2 -16 -18 -20 -6 -12 -10[32,3,2-]
1012910n­184 8 14 2 -16 -18 6 -20 -12 -10[32,21,-2]
1013010n­204 8 -14 2 -16 -18 -6 -20 -12 -10[311,3,2-]
1013110n­194 8 -14 2 16 18 -6 20 12 10[311,21,2-]
Knot-10-132-sm.png 1013210n­134 8 -12 2 -16 -6 -20 -18 -10 -14[23,3,2-]
1013310n44 8 12 2 -14 -18 6 -20 -10 -16[23,21,2-]
1013410n64 8 -12 2 -14 -18 -6 -20 -10 -16[221,3,2-]
1013510n54 8 -12 2 14 18 -6 20 10 16[221,21,2-]
1013610n34 8 10 -14 2 -18 -6 -20 -12 -16[22,22,2-]
1013710n24 8 10 -14 2 -16 -18 -6 -20 -12[22,211,2-]
1013810n14 8 10 -14 2 16 18 -6 20 12[211,211,2-]
1013910n­274 10 -14 -16 2 -18 -20 -6 -8 -12[4,3,3-]
1014010n­294 10 -14 -16 2 18 20 -8 -6 12[4,3,21-]
1014110n­254 10 -14 -16 2 18 -8 -6 20 12[4,21,21-]
1014210n­304 10 -14 -16 2 -18 -20 -8 -6 -12[31,3,3-]
1014310n­264 10 -14 -16 2 -18 -8 -6 -20 -12[31,3,21-]
1014410n­284 10 14 16 2 -18 -20 8 6 -12[31,21,21-]
1014510n­144 8 -12 -18 2 -16 -20 -6 -10 -14[22,3,3-]
1014610n­234 8 -18 -12 2 -16 -20 -6 -10 -14[22,21,21-]
1014710n­244 10 -14 12 2 16 18 -20 8 -6[211,3,21-]
1014810n­124 8 -12 2 -16 -6 -18 -20 -10 -14[(3,2)(3,2-)]
1014910n­114 8 -12 2 16 -6 18 20 10 14[(3,2)(21,2-)]
1015010n94 8 -12 2 -16 -6 -18 -10 -20 -14[(21,2)(3,2-)]
1015110n84 8 -12 2 16 -6 18 10 20 14[(21,2)(21,2-)]
1015210n­366 8 12 2 -16 4 -18 -20 -10 -14[(3,2)-(3,2)]
1015310n­104 8 12 2 -16 6 -18 -20 -10 -14[(3,2)-(21,2)]
1015410n74 8 12 2 -16 6 -18 -10 -20 -14[(21,2)-(21,2)]
1015510n­396 10 14 16 18 4 -20 2 8 -12[-3:2:2]
1015610n­324 12 16 -14 18 2 -8 20 10 6[-3:2:20]
1015710n­426 -10 -18 14 -2 -16 20 8 -4 12[-3:20:20]
1015810n­416 -10 -16 14 -2 -18 8 20 -4 -12[-30:2:2]
1015910n­346 8 10 14 16 -18 -20 2 4 -12[-30:2:20]
1016010n­334 12 -16 -14 -18 2 -8 -20 -10 -6[-30:20:20]
10-161 knot (Perko 1).svg 10161 [lower-alpha 1] 10n­314 12 -16 14 -18 2 8 -20 -10 -6[3:-20:-20]
10162 [lower-alpha 2] 10n­406 10 14 18 16 4 -20 2 8 -12[-30:-20:-20]
10163 [lower-alpha 3] 10n­356 8 10 14 16 -20 -18 2 4 -12[8*-30]
10164 [lower-alpha 4] 10n­386 -10 -12 14 -18 -16 20 -2 -4 -8[8*2:-20]
10165 [lower-alpha 5] 10n­376 8 14 18 16 4 -20 10 2 -12[8*2:.-20]

Higher

Kinoshita-Terasaka & Conway knots Knudemutation.svg
Kinoshita–Terasaka & Conway knots

Seven or fewer crossings

NamePicture Alexander–
Briggs

Rolfsen
Dowker–
Thistlethwaite
Dowker
notation
Conway
notation
Unlink Unlink.png 02
1
Hopf link Hopf Link.png 22
1
L2a1[2]
Solomon's
knot
Solomons-knot-square.svg 42
1
L4a1[4]
Whitehead
link
Whitehead-link.svg 52
1
L5a1[212]
L6a162
3
L6a1
L6a262
2
L6a2
L6a362
1
L6a3
Borromean
rings
Borromean Rings Illusion.png 63
2
L6a4[.1]
L6a563
1
L6a5
L6n1 Valknut-Symbol-3linkchain-closed.svg 63
3
L6n1
L7a172
6
L7a1
L7a272
5
L7a2
L7a372
4
L7a3
L7a472
3
L7a4
L7a572
2
L7a5
L7a672
1
L7a6
L7a773
1
L7a7
L7n172
7
L7n1
L7n272
8
L7n2(6,-8|-10,12,-14,2,-4)

Higher

(36,3)-torus link Torus link (36,3).png
(36,3)-torus link
PictureAlexander–
Briggs–
Rolfsen
Dowker–
Thistlethwaite
Dowker
notation
Conway
notation
3D-Link.PNG 82
1
L8a14
Brunnian-L10a140.svg L10a140 [.3:30]

See also

Notes

  1. Originally listed as both 10161 and 10162 in the Rolfsen table. The error was discovered by Kenneth Perko (see Perko pair).
  2. Listed as 10163 in the Rolfsen table.
  3. Listed as 10164 in the Rolfsen table.
  4. Listed as 10165 in the Rolfsen table.
  5. Listed as 10166 in the Rolfsen table.

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In knot theory, a prime knot or prime link is a knot that is, in a certain sense, indecomposable. Specifically, it is a non-trivial knot which cannot be written as the knot sum of two non-trivial knots. Knots that are not prime are said to be composite knots or composite links. It can be a nontrivial problem to determine whether a given knot is prime or not.

<span class="mw-page-title-main">Borromean rings</span> Three linked but pairwise separated rings

In mathematics, the Borromean rings are three simple closed curves in three-dimensional space that are topologically linked and cannot be separated from each other, but that break apart into two unknotted and unlinked loops when any one of the three is cut or removed. Most commonly, these rings are drawn as three circles in the plane, in the pattern of a Venn diagram, alternatingly crossing over and under each other at the points where they cross. Other triples of curves are said to form the Borromean rings as long as they are topologically equivalent to the curves depicted in this drawing.

In mathematics, the Alexander polynomial is a knot invariant which assigns a polynomial with integer coefficients to each knot type. James Waddell Alexander II discovered this, the first knot polynomial, in 1923. In 1969, John Conway showed a version of this polynomial, now called the Alexander–Conway polynomial, could be computed using a skein relation, although its significance was not realized until the discovery of the Jones polynomial in 1984. Soon after Conway's reworking of the Alexander polynomial, it was realized that a similar skein relation was exhibited in Alexander's paper on his polynomial.

<span class="mw-page-title-main">Torus knot</span> Knot which lies on the surface of a torus in 3-dimensional space

In knot theory, a torus knot is a special kind of knot that lies on the surface of an unknotted torus in R3. Similarly, a torus link is a link which lies on the surface of a torus in the same way. Each torus knot is specified by a pair of coprime integers p and q. A torus link arises if p and q are not coprime. A torus knot is trivial if and only if either p or q is equal to 1 or −1. The simplest nontrivial example is the (2,3)-torus knot, also known as the trefoil knot.

<span class="mw-page-title-main">Hyperbolic link</span> Type of mathematical link

In mathematics, a hyperbolic link is a link in the 3-sphere with complement that has a complete Riemannian metric of constant negative curvature, i.e. has a hyperbolic geometry. A hyperbolic knot is a hyperbolic link with one component.

The Tait conjectures are three conjectures made by 19th-century mathematician Peter Guthrie Tait in his study of knots. The Tait conjectures involve concepts in knot theory such as alternating knots, chirality, and writhe. All of the Tait conjectures have been solved, the most recent being the Flyping conjecture.

<span class="mw-page-title-main">Slice knot</span>

A slice knot is a mathematical knot in 3-dimensional space that bounds an embedded disk in 4-dimensional space.

In mathematics, the Eilenberg–Mazur swindle, named after Samuel Eilenberg and Barry Mazur, is a method of proof that involves paradoxical properties of infinite sums. In geometric topology it was introduced by Mazur and is often called the Mazur swindle. In algebra it was introduced by Samuel Eilenberg and is known as the Eilenberg swindle or Eilenberg telescope.

<span class="mw-page-title-main">Perko pair</span> Prime knot with crossing number 10

In the mathematical theory of knots, the Perko pair, named after Kenneth Perko, is a pair of entries in classical knot tables that actually represent the same knot. In Dale Rolfsen's knot table, this supposed pair of distinct knots is labeled 10161 and 10162. In 1973, while working to complete the classification by knot type of the Tait–Little knot tables of knots up to 10 crossings (dating from the late 19th century), Perko found the duplication in Charles Newton Little's table. This duplication had been missed by John Horton Conway several years before in his knot table and subsequently found its way into Rolfsen's table. The Perko pair gives a counterexample to a "theorem" claimed by Little in 1900 that the writhe of a reduced diagram of a knot is an invariant (see Tait conjectures), as the two diagrams for the pair have different writhes.

<span class="mw-page-title-main">Knot tabulation</span> Attempt to classify and tabulate all possible knots

Ever since Sir William Thomson's vortex theory, mathematicians have tried to classify and tabulate all possible knots. As of May 2008, all prime knots up to 16 crossings have been tabulated. The major challenge of the process is that many apparently different knots may actually be different geometrical presentations of the same topological entity, and that proving or disproving knot equivalence is much more difficult than it at first seems.

<span class="mw-page-title-main">Crossing number (knot theory)</span> Integer-valued knot invariant; least number of crossings in a knot diagram

In the mathematical area of knot theory, the crossing number of a knot is the smallest number of crossings of any diagram of the knot. It is a knot invariant.

<span class="mw-page-title-main">Mathematical visualization</span>

Mathematical phenomena can be understood and explored via visualization. Classically this consisted of two-dimensional drawings or building three-dimensional models, while today it most frequently consists of using computers to make static two or three dimensional drawings, animations, or interactive programs. Writing programs to visualize mathematics is an aspect of computational geometry.

<span class="mw-page-title-main">Twist knot</span> Family of mathematical knots

In knot theory, a branch of mathematics, a twist knot is a knot obtained by repeatedly twisting a closed loop and then linking the ends together. The twist knots are an infinite family of knots, and are considered the simplest type of knots after the torus knots.

<span class="mw-page-title-main">Unknotting number</span> Minimum number of times a specific knot must be passed through itself to become untied

In the mathematical area of knot theory, the unknotting number of a knot is the minimum number of times the knot must be passed through itself to untie it. If a knot has unknotting number , then there exists a diagram of the knot which can be changed to unknot by switching crossings. The unknotting number of a knot is always less than half of its crossing number.

Perko is a surname. Notable people with the surname include:

In knot theory, a knot move or operation is a change or changes which preserve crossing number. Operations are used to investigate whether knots are equivalent, prime or reduced.