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 A301815 #24 Sep 08 2022 08:46:20
%S A301815 0,9,1,8,6,6,7,2,6,2,9,9,1,5,3,9,9,0,3,7,9,6,4,2,2,3,4,0,7,1,8,7,8,0,
%T A301815 9,1,4,1,3,6,2,9,2,8,0,5,6,0,6,4,1,2,1,2,3,6,1,0,8,7,2,0,8,3,7,4,5,6,
%U A301815 2,8,1,9,3,4,9,6,1,8,0,7,0,6,2,9,2,3,4,6
%N A301815 Decimal expansion of gamma / (2*Pi), where gamma is Euler's constant A001620.
%H A301815 G. C. Greubel, <a href="/A301815/b301815.txt">Table of n, a(n) for n = 0..10000</a>
%H A301815 Peter Luschny, <a href="/A301815/a301815.pdf">An expansion for the Bernoulli function</a>
%F A301815 Let beta(r) be the real part of Integral_{-oo..oo} (log(1/2 + i*z)^r / (exp(-Pi*z) + exp(Pi*z))^2) dz, where i denotes the imaginary unit. The constant equals -beta(1) and A301814 equals beta(1/2).
%e A301815 Equals 0.0918667262991539903796422340718780914136292805606412123610872...
%p A301815 evalf(gamma(0)/(2*Pi), 100);
%t A301815 RealDigits[EulerGamma/(2*Pi), 10, 100][[1]] (* _G. C. Greubel_, Aug 11 2018 *)
%o A301815 (PARI) Euler/(2*Pi) \\ _Altug Alkan_, Apr 13 2018
%o A301815 (Magma) R:=RealField(100); EulerGamma(R)/(2*Pi(R)); // _G. C. Greubel_, Aug 27 2018
%Y A301815 Cf. A001620, A301814, A301816, A301817.
%K A301815 nonn,cons
%O A301815 0,2
%A A301815 _Peter Luschny_, Apr 13 2018