%I #7 Jun 18 2020 04:05:36
%S 4,1,8,7,5,7,5,7,8,7,9,4,1,2,5,4,8,0,5,3,4,4,2,1,2,5,6,0,2,8,7,0,4,6,
%T 3,6,1,3,6,5,5,5,1,6,5,4,4,9,2,8,7,0,2,9,4,0,5,2,2,0,0,2,8,0,3,7,7,5,
%U 4,9,6,9,2,5,9,5,2,8,9,0,8,0,2,1,4,8,0,6,7,2,8,4,7,7,8,5,1,1,8,8,8,5,9,4,0,0
%N Decimal expansion of Sum_{primes p} log(p) / (p^2 + p - 1).
%H Steven R. Finch, <a href="https://doi.org/10.1017/9781316997741">Mathematical Constants II</a>, Encyclopedia of Mathematics and Its Applications, Cambridge University Press, Cambridge, 2018, p. 100, p. 169.
%e 0.41875757879412548053442125602870463613655516544928702940522...
%t ratfun = 1 / (p^2 + p - 1); zetas = 0; ratab = Table[konfun = Simplify[ratfun + c/(p^power - 1)] // Together; coefs = CoefficientList[Numerator[konfun], p]; sol = Solve[Last[coefs] == 0, c][[1]]; zetas = zetas + c*Zeta'[power]/Zeta[power] /. sol; ratfun = konfun /. sol, {power, 2, 20}]; Do[Print[N[Sum[Log[p]*ratfun /. p -> Prime[k], {k, 1, m}] + zetas, 100]], {m, 2000, 20000, 2000}]
%Y Cf. A062355, A085609.
%K nonn,cons
%O 0,1
%A _Vaclav Kotesovec_, Jun 18 2020
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