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A245073 Decimal expansion of Integral_{x=0..Pi/2} (x^2/sin(x)) dx. 3
1, 5, 4, 7, 9, 8, 2, 4, 0, 2, 1, 5, 7, 7, 4, 2, 3, 0, 4, 6, 5, 6, 0, 7, 6, 7, 6, 7, 7, 5, 3, 0, 2, 0, 6, 3, 2, 5, 5, 2, 2, 5, 6, 7, 7, 6, 9, 1, 3, 6, 1, 2, 0, 6, 5, 2, 5, 1, 4, 4, 1, 1, 6, 0, 6, 1, 3, 2, 8, 9, 1, 5, 8, 5, 3, 1, 4, 8, 6, 0, 6, 9, 3, 5, 5, 1, 1, 7, 0, 7, 2, 8, 2, 9, 3, 8, 1, 2, 5, 8, 5, 4, 5, 2, 8 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,2

REFERENCES

Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 1.7 Catalan's Constant, p. 57.

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

Eric Weisstein's MathWorld, Apery's Constant

Eric Weisstein's MathWorld, Catalan's Constant

FORMULA

Equals 2*Pi*G - 7*zeta(3)/2, where G is Catalan's constant.

Also equals 4 * Integral_{x=0..1} (arctan(x)^2/x) dx.

EXAMPLE

1.547982402157742304656076767753020632552256776913612065251441160613289...

MATHEMATICA

RealDigits[2*Pi*Catalan - 7*Zeta[3]/2, 10, 105] // First

PROG

(PARI) default(realprecision, 100); 2*Pi*Catalan - 7*zeta(3)/2 \\ G. C. Greubel, Aug 24 2018

(MAGMA) SetDefaultRealField(RealField(100)); R:=RealField(); L:=RiemannZeta();  2*Pi(R)*Catalan(R) - 7*Evaluate(L, 3)/2; // G. C. Greubel, Aug 24 2018

CROSSREFS

Cf. A002117, A006752.

Sequence in context: A324021 A323983 A252666 * A021650 A141269 A136118

Adjacent sequences:  A245070 A245071 A245072 * A245074 A245075 A245076

KEYWORD

nonn,cons,easy

AUTHOR

Jean-Fran├žois Alcover, Jul 11 2014

STATUS

approved

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Last modified October 20 05:49 EDT 2019. Contains 328247 sequences. (Running on oeis4.)