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A200257 Decimal expansion of the circumradius R of cyclic pentagon with sides 2, 3, 5, 7, and 11. 3
5, 5, 0, 6, 2, 9, 9, 6, 3, 8, 6, 6, 8, 1, 3, 1, 8, 1, 9, 8, 8, 4, 3, 9, 5, 0, 6, 3, 3, 1, 3, 1, 8, 8, 1, 6, 6, 3, 2, 5, 3, 5, 3, 9, 0, 5, 5, 1, 8, 2, 7, 9, 2, 0, 0, 0, 3, 9, 6, 8, 0, 3, 8, 8, 6, 5, 0, 1, 1, 9, 7, 7, 6, 2, 9, 3, 6, 2, 9, 1, 1, 1, 8, 8, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Note that for cyclic polygon R does not depend on order of sides.

LINKS

Table of n, a(n) for n=1..85.

Ralph H. Buchholz and James A. MacDougall, Cyclic polygons with rational Sides and Area, Journal of Number Theory, Volume 128, Issue 1, January 2008, Pages 17-48.

Zak Seidov, Figure showing polygon

EXAMPLE

R = 5.5062996386681...

MATHEMATICA

nn=5; L=Sum[Prime[n], {n, nn}]; RealDigits[Re[FindRoot[Sum[ArcSin[Prime[n]/2/R], {n, nn}] == Pi, {R, L/2/Pi}][[1, 2]]]]

CROSSREFS

Sequence in context: A065936 A299625 A021649 * A236023 A200516 A233383

Adjacent sequences:  A200254 A200255 A200256 * A200258 A200259 A200260

KEYWORD

nonn,cons

AUTHOR

Zak Seidov, Nov 15 2011

STATUS

approved

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Last modified August 3 20:43 EDT 2021. Contains 346441 sequences. (Running on oeis4.)