A071279 Kissing number of regular n-gon.

12, 8, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6, 6

Offset: 3

Author

N. J. A. Sloane, Jun 26 2002

Keywords

• nonn
• easy

References

• M. S. Klamkin et al., The kissing number of the square, Math. Magazine, 68 (1995), 128-133.
• L. Zhao and J. Xu, The kissing number of the regular pentagon, Discrete Math., 252 (2002), 293-298.

Links

• Index entries for linear recurrences with constant coefficients, signature (1).

Formula

a(n) = 6 for n >= 5.

G.f.: 2*x^3*(6-2*x-x^2)/(1-x). - Elmo R. Oliveira, Jul 16 2024