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A195103
Decimal expansion of the Dirichlet beta-function at 1/2.
1
6, 6, 7, 6, 9, 1, 4, 5, 7, 1, 8, 9, 6, 0, 9, 1, 7, 6, 6, 5, 8, 6, 9, 0, 9, 2, 9, 3, 0, 0, 2, 4, 8, 4, 8, 2, 2, 5, 1, 5, 9, 7, 8, 2, 9, 7, 4, 2, 9, 3, 7, 0, 9, 7, 7, 4, 9, 7, 9, 8, 6, 5, 7, 3, 2, 1, 7, 6, 1, 6, 0, 8, 7, 8, 9
OFFSET
0,1
COMMENTS
Appears in lattice sums like A088537.
FORMULA
Equals (zeta(1/2,1/4) - zeta(1/2,3/4))/2 where zeta(.,.) is the Hurwitz zeta-function.
EXAMPLE
Equals 0.66769145718960917665869...
MAPLE
DirichletBeta := proc(s) (Zeta(0, s, 1/4)-Zeta(0, s, 3/4))/4^s ; end proc:
x := evalf(DirichletBeta(1/2)) ;
MATHEMATICA
RealDigits[ DirichletBeta[1/2], 10, 75] // First (* Jean-François Alcover, Feb 20 2013, updated Mar 14 2018 *)
PROG
(PARI) zetahurwitz(1/2, 1/4)/2 - zetahurwitz(1/2, 3/4)/2 \\ Charles R Greathouse IV, Jan 31 2018
CROSSREFS
Sequence in context: A160057 A190145 A351214 * A345685 A152485 A372393
KEYWORD
nonn,cons
AUTHOR
R. J. Mathar, Sep 09 2011
STATUS
approved