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A365165
Length of the perimeter of the regular 9-gon with unit circumradius.
3
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
1,1
FORMULA
Equals 9*A272488.
EXAMPLE
6.1563625798620371947937930642806724537...
MATHEMATICA
First[RealDigits[18*Sin[Pi/9], 10, 100]] (* Paolo Xausa, Mar 19 2024 *)
CROSSREFS
Cf. A019845 (5-gon), A010487 (4-gon), A365163 (7-gon), A365164 (8-gon), A272488 (edge length).
Sequence in context: A372065 A370424 A325313 * A019847 A021946 A257704
KEYWORD
nonn,cons
AUTHOR
R. J. Mathar, Aug 24 2023
STATUS
approved