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A280725 Decimal expansion of 22*sin(Pi/22). 5
3, 1, 3, 0, 9, 2, 6, 4, 4, 2, 0, 1, 2, 2, 7, 3, 0, 8, 9, 7, 6, 3, 4, 3, 8, 7, 0, 9, 5, 6, 0, 1, 3, 2, 7, 1, 3, 4, 0, 3, 1, 2, 9, 9, 4, 4, 7, 7, 1, 6, 5, 5, 2, 2, 5, 1, 9, 7, 8, 2, 1, 3, 0, 4, 2, 9, 8, 1, 2, 0, 7, 7, 1, 2, 1, 9, 2, 2, 1, 4, 8, 5, 8, 3, 9, 2, 1, 4, 7, 1, 6, 7, 2, 0, 7, 9, 7, 6, 1, 7, 0, 3, 6, 3, 3 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
The ratio of the perimeter of a regular 11-gon (hendecagon) to its diameter (largest diagonal).
Also least positive root of x^5 - 11x^4 - 484x^3 + 3993x^2 + 43923x - 161051.
LINKS
EXAMPLE
3.130926442012273089763438709560132713403129944771655225197821304298120771...
MAPLE
evalf(22*sin(Pi/22), 100); # Wesley Ivan Hurt, Feb 01 2017
MATHEMATICA
RealDigits[22*Sin[Pi/22], 10, 120][[1]] (* Amiram Eldar, Jun 26 2023 *)
PROG
(PARI) 22*sin(Pi/22)
CROSSREFS
Cf. For other n-gons: A010466 (n=4), 10*A019827 (n=5, 10), A280533 (n=7), A280585 (n=8), A280633 (n=9), A280819 (n=12).
Sequence in context: A079530 A020815 A233931 * A243328 A243332 A156872
KEYWORD
nonn,cons
AUTHOR
Rick L. Shepherd, Jan 07 2017
STATUS
approved

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Last modified March 3 00:46 EST 2024. Contains 370499 sequences. (Running on oeis4.)