

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
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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



