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A220086 Decimal expansion of Gamma(1/7). 23
6, 5, 4, 8, 0, 6, 2, 9, 4, 0, 2, 4, 7, 8, 2, 4, 4, 3, 7, 7, 1, 4, 0, 9, 3, 3, 4, 9, 4, 2, 8, 9, 9, 6, 2, 6, 2, 6, 2, 1, 1, 3, 5, 1, 8, 7, 3, 8, 4, 1, 3, 5, 1, 4, 8, 9, 4, 0, 1, 6, 8, 8, 1, 9, 1, 4, 8, 5, 7, 6, 2, 0, 4, 7, 3, 8, 2, 3, 9, 1, 3, 7, 7, 9, 0, 5, 6 (list; constant; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

(A220086/A220605)*(A220607/A220606) = A160389, which is the case n=7 of (Gamma(1/n)/Gamma(2/n))*(Gamma((n-1)/n)/Gamma((n-2)/n)) = 2*cos(Pi/n).

A220086*A220605*A220606*A220607*A220608*A220609 = (2*Pi)^3/sqrt(7), which is the case n=7 of product(Gamma(i/n), i=1..n-1) = sqrt((2*Pi)^(n-1)/n) (see also the second link to Wikipedia).

Continued fraction expansion: 6, 1, 1, 4, 1, 2, 2, 1, 5, 1, 10, 7, 1,...

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000

Wikipedia, Particular values of the Gamma function: General rational arguments

Wikipedia, Particular values of the Gamma function: Products

Index to sequences related to the Gamma function

FORMULA

Equals Pi*csc(Pi/7)/A220607, where csc is the cosecant function.

EXAMPLE

6.5480629402478244377140933494289962626211351873841351...

MATHEMATICA

RealDigits[Gamma[1/7], 10, 90][[1]]

PROG

(Maxima) fpprec:90; ev(bfloat(gamma(1/7)));

(PARI) default(realprecision, 100); gamma(1/7) \\ G. C. Greubel, Mar 10 2018

(MAGMA) SetDefaultRealField(RealField(100)); Gamma(1/7); // G. C. Greubel, Mar 10 2018

CROSSREFS

Sequence in context: A125089 A171537 A200096 * A094773 A205651 A168239

Adjacent sequences:  A220083 A220084 A220085 * A220087 A220088 A220089

KEYWORD

nonn,cons

AUTHOR

Bruno Berselli, Dec 12 2012

STATUS

approved

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Last modified September 25 01:17 EDT 2018. Contains 315360 sequences. (Running on oeis4.)