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 A257870 #15 Feb 16 2025 08:33:25 %S A257870 1,0,5,8,9,3,5,1,5,5,3,3,1,3,1,5,2,0,7,6,1,3,7,2,2,1,0,6,0,8,5,3,5,1, %T A257870 4,5,4,4,6,5,2,7,0,6,6,5,5,0,2,9,7,5,8,9,8,9,7,6,7,6,5,1,8,8,7,4,2,5, %U A257870 9,0,3,1,1,5,8,9,9,0,2,2,3,3,8,3,2,1,0,5,7,1,8,2,7,9,6,7,6,7,0,7,2,6,5,7,3 %N A257870 Decimal expansion of the Madelung type constant C(1|1/4) (negated). %H A257870 Hassan Chamati and Nicholay S. Tonchev, <a href="http://arxiv.org/abs/cond-mat/0003235">Exact results for some Madelung type constants in the finite-size scaling theory</a>, arXiv:cond-mat/0003235 [cond-mat.stat-mech] (2000). %H A257870 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/MadelungConstants.html">Madelung Constants</a>. %F A257870 2*gamma(1/4)*zeta(1/2). %e A257870 -10.58935155331315207613722106085351454465270665502975898976765... %p A257870 evalf(2*GAMMA(1/4)*Zeta(1/2),120); # _Vaclav Kotesovec_, May 11 2015 %t A257870 RealDigits[2*Gamma[1/4]*Zeta[1/2], 10, 105] // First %o A257870 (PARI) -2*gamma(1/4)*zeta(1/2) \\ _Charles R Greathouse IV_, May 11 2015 %Y A257870 Cf. A257871, A257872. %K A257870 nonn,cons,easy %O A257870 2,3 %A A257870 _Jean-François Alcover_, May 11 2015