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A091476 Decimal expansion of Pi^2/4. 7
2, 4, 6, 7, 4, 0, 1, 1, 0, 0, 2, 7, 2, 3, 3, 9, 6, 5, 4, 7, 0, 8, 6, 2, 2, 7, 4, 9, 9, 6, 9, 0, 3, 7, 7, 8, 3, 8, 2, 8, 4, 2, 4, 8, 5, 1, 8, 1, 0, 1, 9, 7, 6, 5, 6, 6, 0, 3, 3, 3, 7, 3, 4, 4, 0, 5, 5, 0, 1, 1, 2, 0, 5, 6, 0, 4, 8, 0, 1, 3, 1, 0, 7, 5, 0, 4, 4, 3, 3, 5, 0, 9, 2, 9, 6, 3, 8, 0, 5, 7, 9, 5 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Integral(x=0..Pi) x*sin(x)/(1+cos(x)^2) dx.

Also equals integral(x=0..1) log((1+x)/(1-x))/x dx. [Jean-François Alcover, May 13 2013]

LINKS

Table of n, a(n) for n=1..102.

T. Piezas III, Golden ratio and nested radicals

Eric Weisstein's World of Mathematics, Definite Integral

FORMULA

Equals integral_{x=0..infinity} K_0(x)^2 dx, where K_0 is a modified Bessel function (see Gradstein-Ryshik 6.576.4). - R. J. Mathar, Oct 09 2015

Equals A003881 * A000796. - R. J. Mathar, Oct 09 2015

EXAMPLE

2.467401...

CROSSREFS

Sequence in context: A142473 A132426 A072646 * A257578 A272665 A114431

Adjacent sequences:  A091473 A091474 A091475 * A091477 A091478 A091479

KEYWORD

nonn,cons

AUTHOR

Eric W. Weisstein, Jan 13 2004

STATUS

approved

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Last modified August 22 22:36 EDT 2017. Contains 290952 sequences.