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A172293 a(n) = number of prime knots with determinant 2n+1 and signature 0. 9
1, 0, 1, 0, 3, 0, 2, 0, 2, 0, 1, 0, 2, 0, 2, 0, 0, 0, 2, 0, 1, 0, 3, 0, 2, 0, 1, 0, 0, 0, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

REFERENCES

Peter R. Cromwell, Knots and Links, Cambridge University Press, 2004. See p. 146, Fig. 6.6.

LINKS

Table of n, a(n) for n=0..30.

EXAMPLE

a(0) = 1 because the only prime knot with determinant 2*0+1=1 and s=0 is 0_1, the unknot.

a(2) = 1 because the only prime knot with determinant 2*2+1=5 and s=0 is 4_1, the figure-8 knot.

a(4) = 3 because the three prime knot with determinant 2*4+1=9 and s=0 are 6_1, 8_20, and 9_46.

CROSSREFS

Cf. A002863.

First column of A172184.

Sequence in context: A166243 A118514 A190544 * A161970 A230446 A260737

Adjacent sequences:  A172290 A172291 A172292 * A172294 A172295 A172296

KEYWORD

nonn,more

AUTHOR

Jonathan Vos Post, Nov 20 2010

EXTENSIONS

Partially edited by N. J. A. Sloane, Jun 10 2019

STATUS

approved

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Last modified May 25 17:53 EDT 2020. Contains 334595 sequences. (Running on oeis4.)