A172444 Number of prime knots up to nine crossings with determinant 2n+1 and signature 4.
0, 0, 1, 0, 0, 0, 2, 0, 2, 0, 2, 0, 1, 0, 1, 0, 3, 0, 2, 0, 2, 0, 1, 0, 0, 0, 0, 0, 1
Offset: 0
Examples
a(2) = 1 because the only prime knot with no more than 9 crossings with determinant 2*2+1=5 and s=4 is 5_1, the Solomon's seal knot. a(6) = 2 because the only prime knots with no more than 9 crossings with determinant 2*6+1=13 and s=4 are 7_3 and 9_43.
References
- Peter R. Cromwell, Knots and Links, Cambridge University Press, November 15, 2004.
Extensions
Edited by Andrey Zabolotskiy, Apr 29 2024
Comments