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A172441 Number of prime knots up to nine crossings with determinant 2n+1 and signature 2. 6
0, 1, 0, 2, 0, 2, 0, 3, 0, 2, 0, 4, 0, 5, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 2, 0, 1, 0, 0, 0, 0, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,4
COMMENTS
Adapted from Figure 6.6. The prime knots up to nine crossings separated by signature and determinant, p. 146, Cromwell. Second column of A172184.
REFERENCES
Peter R. Cromwell, Knots and Links, Cambridge University Press, 2004.
LINKS
EXAMPLE
a(1) = 1 because the only prime knot with no more than 9 crossings with determinant 2*1+1=3 and s=2 is 3_1, the left-handed trefoil.
a(3) = 2 because the only prime knots with no more than 9 crossings with determinant 2*3+1=7 and s=2 are 5_2 and 9_42.
CROSSREFS
Sequence in context: A301979 A183063 A318979 * A359495 A053399 A322996
KEYWORD
nonn,fini,full,changed
AUTHOR
Jonathan Vos Post, Nov 20 2010
EXTENSIONS
Edited by Andrey Zabolotskiy, Apr 29 2024
STATUS
approved

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Last modified May 13 23:15 EDT 2024. Contains 372524 sequences. (Running on oeis4.)