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 A090734 #23 Jul 29 2025 06:07:52 %S A090734 1,8,3,9,3,9,9,0,8,4,0,4,5,0,4,7,0,6,6,2,4,7,3,0,5,4,7,9,5,6,7,2,3,0, %T A090734 4,7,6,4,2,2,7,8,3,5,9,4,8,1,7,7,3,0,5,7,9,1,6,7,9,7,8,6,7,7,5,7,2,8, %U A090734 1,8,2,5,2,6,4,3,7,3,3,5,2,2,8,4,1,5,8,7,4,1,3,3,9,6,6,0,3,7,7,6,0,2,9,3,6 %N A090734 Decimal expansion of 4th Madelung constant (negated). %D A090734 Steven R. Finch, Mathematical Constants, Cambridge, 2003, p. 77. %F A090734 M_4 = -8*(5-3*sqrt(2))*zeta(1/2)*zeta(-1/2) = -8 *(A157122-6) * A059750 * A211113. %e A090734 -1.83939908404504706624730547956723047642278359481773... %t A090734 RealDigits[8*(5 - 3*Sqrt[2])*Zeta[1/2]*Zeta[-1/2], 10, 120][[1]] (* _Amiram Eldar_, May 26 2023 *) %o A090734 (PARI) 8*(5-3*sqrt(2))*zeta(1/2)*zeta(-1/2) \\ _Charles R Greathouse IV_, Jun 07 2016 %Y A090734 Cf. A059750, A088537, A085469. %K A090734 cons,nonn %O A090734 1,2 %A A090734 _Benoit Cloitre_, Jan 18 2004