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A086241
Decimal expansion of value to which Sum_{k>=2} d(k)/prime(k) appears to converge, where d(k)=-1 if p mod 3 = 1, d(k)=+1 if p mod 3 = 2 and d(k)=0 if p mod 3 = 0.
5
6, 4, 1, 9, 4, 4, 8, 3, 8, 5, 3, 3, 1, 9, 5, 7, 0, 8, 6, 6, 1, 3, 9, 2, 6, 3, 9, 7, 2, 1, 7, 3, 4, 3, 1, 6, 6, 7, 5, 4, 1, 1, 0, 4, 4, 0, 1, 5, 8, 8, 9, 6, 5, 4, 9, 0, 8, 1, 7, 0, 8, 4, 5, 1, 3, 1, 7, 3, 3, 2, 8, 2, 6, 9, 0, 7, 3, 7, 2, 3, 3, 5, 9, 8, 1, 7, 4, 1, 5, 9, 9, 4, 5, 6, 0, 6, 5, 7
OFFSET
0,1
COMMENTS
It is not known if this series actually converges.
REFERENCES
Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, pp. 94-98.
LINKS
Richard J. Mathar, Table of Dirichlet L-series..., arXiv:1008.2547 [math.NT], 2010-2015, value of S(m=3,r=2,s=1).
Eric Weisstein's World of Mathematics, Prime Sums.
FORMULA
Equals A161529 + A368644. - Amiram Eldar, Jan 02 2024
EXAMPLE
0.64194483853319570866139263972173431667541104401588965490817...
MATHEMATICA
S[m_, n_, s_] := (t = 1; sums = 0; difs = 1; While[Abs[difs] > 10^(-digits - 5) || difs == 0, difs = (MoebiusMu[t]/t) * Log[If[s*t == 1, DirichletL[m, n, s*t], Sum[Zeta[s*t, j/m]*DirichletCharacter[m, n, j]^t, {j, 1, m}]/m^(s*t)]]; sums = sums + difs; t++]; sums); $MaxExtraPrecision = 1000; digits = 121; RealDigits[Chop[N[-S[3, 2, 1], digits]], 10, digits-1][[1]] (* Vaclav Kotesovec, Jan 22 2021 *)
CROSSREFS
Sequence in context: A324034 A365319 A343614 * A378412 A204023 A360984
KEYWORD
nonn,cons,hard
AUTHOR
Eric W. Weisstein, Jul 13 2003
EXTENSIONS
More digits from R. J. Mathar, Jul 28 2010
Sign typo in definition corrected by R. J. Mathar, Aug 01 2010
STATUS
approved

  NODES
COMMUNITY 1
INTERN 1