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A280585
Decimal expansion of 8*sin(Pi/8).
4
3, 0, 6, 1, 4, 6, 7, 4, 5, 8, 9, 2, 0, 7, 1, 8, 1, 7, 3, 8, 2, 7, 6, 7, 9, 8, 7, 2, 2, 4, 3, 1, 9, 0, 9, 3, 4, 0, 9, 0, 7, 5, 6, 4, 9, 9, 8, 8, 5, 0, 1, 6, 3, 3, 1, 4, 7, 0, 4, 0, 5, 0, 8, 5, 0, 2, 0, 3, 6, 8, 2, 7, 1, 6, 8, 0, 7, 1, 7, 5, 3, 7, 8, 9, 6, 1, 1, 0, 2, 8, 2, 7, 3, 8, 2, 6, 8, 3, 7, 7, 1, 8, 7, 3, 9
OFFSET
1,1
COMMENTS
Decimal expansion of the ratio of the perimeter of a regular 8-gon (octagon) to its diameter (largest diagonal).
FORMULA
Equals 8*A182168.
EXAMPLE
3.061467458920718173827679872243190934090756499885016331470405085020368271...
MAPLE
evalf(8*sin(Pi/8), 100); # Wesley Ivan Hurt, Feb 01 2017
MATHEMATICA
RealDigits[8*Sin[Pi/8], 10, 120][[1]] (* Amiram Eldar, Jun 26 2023 *)
PROG
(PARI) 8*sin(Pi/8)
CROSSREFS
Cf. For other n-gons: A010466 (n=4), 10*A019827 (n=5, 10), A280533 (n=7), A280633 (n=9), A280725 (n=11), A280819 (n=12).
Cf. A182168.
Sequence in context: A117784 A257896 A268978 * A359218 A197807 A111074
KEYWORD
nonn,cons
AUTHOR
Rick L. Shepherd, Jan 05 2017
STATUS
approved