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A093828 Decimal expansion of (3*Pi)/8. 4
1, 1, 7, 8, 0, 9, 7, 2, 4, 5, 0, 9, 6, 1, 7, 2, 4, 6, 4, 4, 2, 3, 4, 9, 1, 2, 6, 8, 7, 2, 9, 8, 1, 3, 5, 8, 1, 5, 7, 3, 9, 3, 8, 5, 2, 4, 7, 6, 5, 6, 6, 4, 6, 8, 2, 8, 6, 5, 6, 0, 4, 2, 2, 2, 1, 1, 5, 4, 3, 1, 1, 5, 2, 3, 5, 7, 3, 2, 8, 3, 7, 4, 4, 8, 5, 5, 1, 3, 0, 5, 9, 5, 0, 3, 2, 9, 3, 9, 0, 0, 4, 9 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Area of an astroid with a = 1.

LINKS

Harry J. Smith, Table of n, a(n) for n = 1..20000

Eric Weisstein's World of Mathematics, Astroid

FORMULA

Equals Integral_{x>0} sin(x)^3/x^3. - Jean-Fran├žois Alcover, Jun 04 2013

From Amiram Eldar, Aug 02 2020: (Start)

Equals arctan(1 + sqrt(2)).

Equals Integral_{x=0..1} x^(3/2)/sqrt(1-x) dx. (End)

EXAMPLE

1.1780972450961724644234912687298135815739385247656646...

MAPLE

evalf[110](3*Pi*(1/8)); # G. C. Greubel, Aug 11 2019

MATHEMATICA

RealDigits[3*Pi/8, 10, 105][[1]] (* G. C. Greubel, Aug 11 2019 *)

PROG

(PARI) { default(realprecision, 20080); x=3*Pi/8; for (n=1, 20000, d=floor(x); x=(x-d)*10; write("b093828.txt", n, " ", d)); } \\ Harry J. Smith, Jun 18 2009

(MAGMA) SetDefaultRealField(RealField(110)); R:= RealField(); 3*Pi(R)/8; // G. C. Greubel, Aug 11 2019

(Sage) numerical_approx(3*pi/8, digits=110) # G. C. Greubel, Aug 11 2019

CROSSREFS

Cf. A161685 (continued fraction). - Harry J. Smith, Jun 18 2009

Sequence in context: A088396 A199723 A188485 * A010514 A073004 A256670

Adjacent sequences:  A093825 A093826 A093827 * A093829 A093830 A093831

KEYWORD

nonn,cons,easy,changed

AUTHOR

Eric W. Weisstein, Apr 16 2004

STATUS

approved

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Last modified August 10 02:02 EDT 2020. Contains 336365 sequences. (Running on oeis4.)