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A090551 Decimal expansion of sqrt(3) - Pi/2. 0
1, 6, 1, 2, 5, 4, 4, 8, 0, 7, 7, 3, 9, 8, 0, 6, 7, 4, 2, 9, 6, 1, 2, 4, 6, 4, 9, 8, 6, 6, 1, 2, 0, 9, 2, 4, 8, 4, 4, 2, 2, 0, 5, 5, 4, 1, 2, 2, 8, 2, 7, 7, 1, 7, 5, 6, 8, 3, 3, 4, 6, 8, 3, 2, 9, 8, 0, 2, 4, 8, 1, 3, 7, 6, 5, 6, 9, 5, 5, 3, 7, 7, 6, 7, 1, 2, 8, 7, 7, 4, 0, 8, 6, 1, 9, 0, 0, 4, 1, 6, 8, 4, 5, 5, 2 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Decimal expansion of the real number quantifying the area of the Apollonian gasket of three congruent circles of radius 1.

General solution: This constant is the ratio of r^2, where r is the radius of three congruent circles forming a Apollonian gasket, to the area of that Apollonian gasket.

sqrt(3)-pi/2 is the area enclosed between three identical osculating circles of unit radius. - Lekraj Beedassy, Apr 12 2006

LINKS

Table of n, a(n) for n=0..104.

Eric Weisstein's World of Mathematics, Apollonian Gasket.

FORMULA

a(n) = 3^(1/2) - pi/2.

EXAMPLE

0.16125448077398067429612464986612...

RealDigits[ Sqrt[3] - Pi/2, 10, 105][[1]]

MATHEMATICA

RealDigits[N[Sqrt[3] - Pi/2, 300]][[1]] (* Vladimir Joseph Stephan Orlovsky, Jul 03 2011 *)

CROSSREFS

Cf. A002194; A019669.

Sequence in context: A187110 A013672 A019946 * A220782 A274617 A070682

Adjacent sequences:  A090548 A090549 A090550 * A090552 A090553 A090554

KEYWORD

cons,nonn

AUTHOR

Christopher M. Tomaszewski (cmt1288(AT)comcast.net), Feb 01 2004

EXTENSIONS

More terms from Robert G. Wilson v, Feb 09 2004

Edited by N. J. A. Sloane, Jul 05 2008 at the suggestion of Rick L. Shepherd

STATUS

approved

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Last modified February 18 20:32 EST 2018. Contains 299330 sequences. (Running on oeis4.)