The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A086054 Decimal expansion of Pi*log(2). 6
 2, 1, 7, 7, 5, 8, 6, 0, 9, 0, 3, 0, 3, 6, 0, 2, 1, 3, 0, 5, 0, 0, 6, 8, 8, 8, 9, 8, 2, 3, 7, 6, 1, 3, 9, 4, 7, 3, 3, 8, 5, 8, 3, 7, 0, 0, 3, 6, 9, 2, 8, 6, 2, 9, 4, 3, 2, 5, 7, 9, 5, 2, 5, 3, 1, 9, 4, 3, 0, 8, 5, 4, 9, 1, 7, 6, 7, 4, 1, 9, 8, 6, 4, 3, 0, 3, 2, 8, 9, 6, 1, 6, 1, 0, 6, 6, 3, 0, 2, 5, 0, 5, 7, 6, 1 (list; constant; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Madelung constant b2(2), negated. LINKS Eric Weisstein's World of Mathematics, Madelung Constants FORMULA Pi*log(2) = -(8/3)*int(log(x)/sqrt(1+4*x-4*x^2), x=0..1). - John M. Campbell, Feb 07 2012 Pi*log(2) = int((x/sin(x))^2, x=0..Pi/2) = int(log(x^2+1)/(x^2+1), x=0..infinity) = int(-log(cos(x)), x=-Pi/2..Pi/2) = int(arctan(1/x)^2, x=0..infinity). - Jean-François Alcover, May 30 2013 From Amiram Eldar, Jul 11 2020: (Start) Equals Integral_{x=-1..1} arcsin(x) dx / x. Equals Integral_{x=-Pi/2..Pi/2} x*cot(x) dx. (End) EXAMPLE 2.1775860903036021305006888982376139... MATHEMATICA RealDigits[Pi Log[2], 10, 120][[1]] (* Harvey P. Dale, Dec 31 2011 *) CROSSREFS Cf. A000796 (Pi), A002162 (log(2)). Sequence in context: A072280 A217106 A329995 * A256392 A011134 A157240 Adjacent sequences:  A086051 A086052 A086053 * A086055 A086056 A086057 KEYWORD nonn,cons,easy AUTHOR Eric W. Weisstein, Jul 07 2003 EXTENSIONS Corrected by Antti Ahti (antti.ahti(AT)tkk.fi), Nov 17 2004 More terms from Benoit Cloitre, May 21 2005 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified September 18 22:34 EDT 2021. Contains 347548 sequences. (Running on oeis4.)