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A365164
Length of the perimeter of the regular octagon with unit circumradius.
2
6, 1, 2, 2, 9, 3, 4, 9, 1, 7, 8, 4, 1, 4, 3, 6, 3, 4, 7, 6, 5, 5, 3, 5, 9, 7, 4, 4, 4, 8, 6, 3, 8, 1, 8, 6, 8, 1, 8, 1, 5, 1, 2, 9, 9, 9, 7, 7, 0, 0, 3, 2, 6, 6, 2, 9, 4, 0, 8, 1, 0, 1, 7, 0, 0, 4, 0, 7, 3, 6, 5, 4, 3, 3, 6, 1, 4, 3, 5, 0, 7, 5, 7, 9, 2, 2, 2, 0, 5, 6, 5, 4, 7, 6, 5, 3, 6, 7, 5, 4, 3, 7, 4, 7, 8, 8, 6, 1, 8
OFFSET
1,1
FORMULA
Equals 8*A101464.
EXAMPLE
6.122934917841436347655359744486...
MATHEMATICA
f[R_, s_] := 2*R*s*Sin[Pi/s]; a[n_] := RealDigits[f[1, 8], 10, n][[1]]; a[109] (* Robert P. P. McKone, Aug 24 2023 *)
CROSSREFS
Cf. A019845 (5-gon), A010487 (4-gon), A365163 (7-gon), A365165 (9-gon), A101464 (edge length), A010466 (area).
Sequence in context: A010135 A176401 A325977 * A153736 A165070 A246711
KEYWORD
cons,nonn
AUTHOR
R. J. Mathar, Aug 24 2023
STATUS
approved