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A157700 Decimal expansion of log(4/(1 + sqrt(2))). 1
5, 0, 4, 9, 2, 0, 7, 7, 4, 1, 0, 0, 3, 4, 7, 5, 9, 3, 6, 0, 1, 8, 5, 4, 9, 1, 7, 9, 3, 6, 5, 6, 0, 8, 2, 7, 1, 2, 2, 8, 3, 9, 9, 4, 0, 4, 5, 8, 8, 7, 5, 0, 9, 7, 4, 8, 8, 0, 6, 4, 4, 1, 0, 3, 3, 3, 4, 1, 0, 0, 5, 9, 7, 1, 7, 3, 6, 3, 3, 4, 3, 3, 7, 8, 0, 1, 9, 7, 6, 2, 0, 8, 2, 5, 8, 1, 3, 3, 2, 2, 2, 7, 2, 6, 3 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Equals Sum_{n>=2, n even} binomial(2n,n)/(n*4^n) = A016627-A091648.

LINKS

G. C. Greubel, Table of n, a(n) for n = 0..10000

D. H. Lehmer, Interesting series involving the Central Binomial Coefficient, Am. Math. Monthly 92, no 7 (1985) 449-457.

Index entries for transcendental numbers

EXAMPLE

0.5049207741003475936018...

MAPLE

log(4/(1+sqrt(2))) ;

MATHEMATICA

RealDigits[Log[4/(1+Sqrt[2])], 10, 120][[1]] (* Harvey P. Dale, Jun 08 2014 *)

PROG

(PARI) default(realprecision, 100); log(4/(1+sqrt(2))) \\ G. C. Greubel, Oct 02 2018

(MAGMA) SetDefaultRealField(RealField(100)); Log(4/(1+Sqrt(2))); // G. C. Greubel, Oct 02 2018

CROSSREFS

Sequence in context: A198839 A062521 A271951 * A099645 A220412 A199092

Adjacent sequences:  A157697 A157698 A157699 * A157701 A157702 A157703

KEYWORD

cons,easy,nonn

AUTHOR

R. J. Mathar, Mar 04 2009

STATUS

approved

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Last modified November 13 04:20 EST 2019. Contains 329085 sequences. (Running on oeis4.)