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A271523
Decimal expansion of the real part of the Dirichlet function eta(z), at z=i, the imaginary unit.
4
5, 3, 2, 5, 9, 3, 1, 8, 1, 7, 6, 3, 0, 9, 6, 1, 6, 6, 5, 7, 0, 9, 6, 5, 0, 0, 8, 1, 9, 7, 3, 1, 9, 0, 4, 4, 7, 2, 7, 7, 8, 5, 7, 6, 8, 1, 4, 3, 4, 9, 2, 1, 9, 2, 2, 3, 9, 7, 4, 8, 7, 2, 5, 9, 5, 9, 4, 3, 8, 2, 6, 3, 1, 5, 6, 3, 1, 1, 1, 7, 7, 6, 6, 8, 6, 6, 0, 8, 9, 6, 4, 8, 9, 7, 7, 9, 5, 5, 7, 2, 2, 4, 1, 2, 0
OFFSET
0,1
COMMENTS
The corresponding imaginary part of eta(i) is in A271524.
LINKS
Eric Weisstein's World of Mathematics, Dirichlet Eta Function
FORMULA
Equals real(eta(i)).
EXAMPLE
0.53259318176309616657096500819731904472778576814349219223974872595...
MATHEMATICA
First[RealDigits[Re[(1 - 2^(1 - I))*Zeta[I]], 10, 110]] (* Robert Price, Apr 09 2016 *)
PROG
(PARI) \\ The Dirichlet eta function (fails for z=1):
direta(z)=(1-2^(1-z))*zeta(z);
real(direta(I)) \\ Evaluation
CROSSREFS
Cf. A002162 (eta(1)), A179311 (real(zeta(i))), A179836 (imag(-zeta(i))), A271524 (imag(eta(i))), A271525 (real(eta'(i))), A271526(-imag(eta'(i))).
Sequence in context: A373666 A009661 A023576 * A352903 A125844 A171025
KEYWORD
nonn,cons
AUTHOR
Stanislav Sykora, Apr 09 2016
STATUS
approved