%I #16 Jul 16 2021 11:29:45
%S 1,3,2,2,8,0,9,9,7,5,0,4,2,1,2,5,1,4,5,2,7,0,9,8,2,1,1,5,8,5,7,8,5,5,
%T 1,8,6,8,0,6,4,8,0,0,9,9,9,9,5,5,0,3,1,4,5,8,8,4,7,4,5,0,1,9,2,4,1,4,
%U 2,9,1,5,7,1,9,9,4,0,4,2,9,3,8,7,7,8,3,9,4,6,4
%N Decimal expansion of zeta'(-20) (the derivative of Riemann's zeta function at -20).
%H G. C. Greubel, <a href="/A266275/b266275.txt">Table of n, a(n) for n = 3..1500</a>
%F zeta'(-20) = (9280784638125*zeta(21))/(8*Pi^20) = - log(A(20)).
%F Equals (174611/1320)*(zeta(21)/zeta(20)).
%e 132.28099750421251452709821158578551868064800999955031458847450192414...
%t RealDigits[N[Zeta'[-20], 100]]
%Y Cf. A075700 (zeta'(0)), A084448 (zeta'(-1)), A240966 (zeta'(-2)), A259068 (zeta'(-3)), A259069 (zeta'(-4)), A259070 (zeta'(-5)), A259071 (zeta'(-6)), A259072 (zeta'(-7)), A259073 (zeta'(-8)), A266260 (zeta'(-9)), A266261 (zeta'(-10)), A266262 (zeta'(-11)), A266263 (zeta'(-12)), A260660 (zeta'(-13)), A266264 (zeta'(-14)), A266270 (zeta'(-15)), A266271 (zeta'(-16)), A266272 (zeta'(-17)), A266273 (zeta'(-18)), A266274 (zeta'(-19)).
%K nonn,cons
%O 3,2
%A _G. C. Greubel_, Dec 26 2015
%E Offset corrected by _Rick L. Shepherd_, May 30 2016