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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 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.)