This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A256929 #24 Feb 16 2025 08:33:25
%S A256929 1,0,5,0,0,9,1,1,5,0,0,9,4,8,2,2,1,0,0,1,7,5,7,9,1,6,9,1,6,5,7,9,3,8,
%T A256929 5,9,5,3,4,0,4,4,6,1,1,3,7,4,9,2,8,6,9,0,3,3,2,6,0,3,0,5,7,2,3,2,0,4,
%U A256929 7,3,3,6,9,3,0,2,8,4,0,0,6,3,7,4,8,2,8,2,7,9,7,8,0,8,6,1,6,7,6,3,8,9,0
%N A256929 Decimal expansion of Sum_{k>=1} (zeta(2*k)/k)*(1/2)^(4*k).
%D A256929 H. M. Srivastava and Junesang Choi, Zeta and q-Zeta Functions and Associated Series and Integrals, Elsevier Insights, 2011, p. 272, eq. (30).
%H A256929 Eric Weisstein's MathWorld, <a href="https://mathworld.wolfram.com/RiemannZetaFunction.html">Riemann Zeta Function</a>.
%H A256929 Wikipedia, <a href="http://en.wikipedia.org/wiki/Riemann_zeta_function">Riemann zeta function</a>.
%F A256929 Equals log(Gamma(3/4)*Gamma(5/4)) = log(A068465*A068467).
%F A256929 Equals log(Pi/(2*sqrt(2))) = log(A093954).
%F A256929 Equals -Sum_{k>=1} log(1 - 1/(4*k)^2). - _Amiram Eldar_, Aug 12 2020
%e A256929 0.1050091150094822100175791691657938595340446113749286903326...
%t A256929 RealDigits[Log[Pi/(2*Sqrt[2])], 10, 103] // First
%o A256929 (PARI) log(Pi/(2*sqrt(2))) \\ _Amiram Eldar_, Oct 12 2024
%Y A256929 Cf. A068465, A068467, A093954, A256930.
%K A256929 nonn,cons,easy
%O A256929 0,3
%A A256929 _Jean-François Alcover_, Apr 13 2015
%E A256929 Name corrected by _Amiram Eldar_, Oct 12 2024