A365165 Length of the perimeter of the regular 9-gon with unit circumradius.

6, 1, 5, 6, 3, 6, 2, 5, 7, 9, 8, 6, 2, 0, 3, 7, 1, 9, 4, 7, 9, 3, 7, 9, 3, 0, 6, 4, 2, 8, 0, 6, 7, 2, 4, 5, 3, 7, 3, 5, 5, 0, 0, 6, 1, 5, 2, 5, 4, 8, 9, 1, 3, 1, 2, 3, 7, 0, 8, 7, 2, 9, 5, 8, 3, 2, 4, 8, 6, 5, 7, 4, 6, 6, 3, 7, 3, 9, 6, 7, 9, 2, 1, 5, 5, 4, 2, 3, 2, 8, 2, 0, 9, 3, 4, 5, 9, 8, 5, 5

Offset: 1

Author

R. J. Mathar, Aug 24 2023

Keywords

• nonn
• cons

Examples

			6.1563625798620371947937930642806724537...
		

Links

• Paolo Xausa, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A019845 (5-gon), A010487 (4-gon), A365163 (7-gon), A365164 (8-gon), A272488 (edge length).

Programs

Mathematica

First[RealDigits[18*Sin[Pi/9], 10, 100]] (* Paolo Xausa, Mar 19 2024 *)

Formula

Equals 9*A272488.