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A360500
Decimal expansion of the unique positive root to zeta(s) + zeta'(s) = 0, where zeta is the Riemann zeta function and zeta' is the derivative of zeta.
0
1, 6, 8, 0, 4, 1, 7, 3, 5, 9, 2, 0, 4, 0, 3, 7, 5, 4, 7, 7, 6, 7, 3, 5, 0, 3, 7, 5, 0, 6, 0, 3, 3, 1, 9, 4, 4, 9, 2, 1, 1, 9, 1, 5, 8, 9, 1, 4, 7, 3, 9, 5, 2, 5, 1, 1, 8, 7, 8, 6, 5, 1, 3, 0, 7, 4, 1, 5, 0, 4, 0, 3, 8, 7, 9, 8, 2, 1, 6, 5, 7, 8, 1, 0, 7, 5, 6, 1, 0, 6, 3, 5, 9, 6, 0, 6, 1, 5
OFFSET
1,2
COMMENTS
Denote this root as s_0, then Sum_{n>=1} log(n)/n^s > Sum_{n>=1} 1/n^s if and only if 1 < s < s_0; Sum_{n>=1} log(n)/n^s < Sum_{n>=1} 1/n^s if and only if s > s_0.
EXAMPLE
Uniquely for s_0 = 1.68041735920403754776..., we have Sum_{n>=1} log(n)/n^(s_0) = Sum_{n>=1} 1/n^(s_0).
MATHEMATICA
RealDigits[s /. FindRoot[Zeta[s] + Zeta'[s] == 0, {s, 2}, WorkingPrecision -> 120]][[1]] (* Amiram Eldar, Jun 25 2023 *)
PROG
(PARI) solve(x=1.5, 2, zeta(x)+zeta'(x))
CROSSREFS
Sequence in context: A268508 A021151 A200116 * A308314 A097909 A143819
KEYWORD
nonn,cons
AUTHOR
Jianing Song, Feb 09 2023
STATUS
approved