login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A332614
a(n) is the smallest index k such that Sum_{m=1..k} 1/z(m) > n where z(m) is the imaginary part of the m-th nontrivial zero of the Riemann zeta function, n=0,1,2,...
8
1, 93, 621, 2437, 7438, 19490, 45996, 100462, 206617, 404855, 762155, 1387088, 2452209, 4227039, 7126088, 11778044, 19124514, 30559702, 48126380, 74788784, 114809974, 174270215, 261774713, 389414312, 574062463, 839117171, 1216829213, 1751399577, 2503082172, 3553595368
OFFSET
0,2
COMMENTS
Because series Sum_{m>=1} 1/z(m) is divergent this sequence is infinite.
Sum_{m>=1} 1/z(m)^2 = 0.0231049931...; see A332645.
Sum_{m>=1} 1/(1/4 + z(m)^2) = 0.023095708966... see A074760.
Sum_{m>=1} 1/(1/2 + i*z(m))^2 + 1/(1/2 - i*z(m))^2 = -0.046154317... see A245275.
Sum_{m>=1} 1/(1/2 + i*z(m))^3 + 1/(1/2 - i*z(m))^3 = -0.00011115823... see A245276.
a(11)-a(39) computed by David Platt, Mar 20 2020.
LINKS
Kano Kono, Vieta's Formulas on Completed Riemann Zeta, Alien's Mathematics.
EXAMPLE
a(0)=1 because 1/z(1) = 0.070747749954285585596 > 0
a(1)=93 because Sum_{m=1..93} 1/z(m) = 1.00082895080028509266 > 1
a(2)=621 because Sum_{m=1..621} 1/z(m) = 2.00017203211984838994 > 2.
MATHEMATICA
aa = {}; kk = 0; b = 0; Do[b = b + N[1/Im[ZetaZero[n]], 30];
If[b > kk, AppendTo[aa, n]; kk = kk + 1]; , {n, 1, 1000000}]; aa
KEYWORD
nonn
AUTHOR
Artur Jasinski, Feb 17 2020
EXTENSIONS
More terms from Artur Jasinski, Feb 21 2020
STATUS
approved