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 A256988 #14 Feb 16 2025 08:33:25
%S A256988 1,2,3,4,6,5,8,1,9,0,1,7,3,0,9,9,5,3,8,1,5,1,0,7,4,0,3,0,6,0,5,5,4,6,
%T A256988 7,2,5,2,6,5,2,9,6,0,6,6,1,6,7,9,2,6,2,3,2,8,4,3,7,7,4,9,0,5,6,0,9,2,
%U A256988 7,5,0,9,3,2,0,0,9,4,1,9,0,5,3,3,0,2,8,1,5,4,3,8,0,9,3,0,8,2,9,7,1,1,6,8
%N A256988 Decimal expansion of Sum_{k>=1} H(k)^3/k^2 where H(k) is the k-th harmonic number.
%H A256988 Alois Panholzer and Helmut Prodinger, <a href="http://www.emis.de/journals/SLC/wpapers/s55panprod.pdf">Computer-free evaluation of an infinite double sum via Euler sums</a> Séminaire Lotharingien de Combinatoire 55 (2005), Article B55a
%H A256988 Eric Weisstein's MathWorld, <a href="https://mathworld.wolfram.com/HarmonicNumber.html">Harmonic Number.</a>
%F A256988 Equals 10*zeta(5) + zeta(2)*zeta(3) or, 10*zeta(5) + (Pi^2/6)*zeta(3).
%e A256988 12.346581901730995381510740306055467252652960661679262328437749...
%t A256988 RealDigits[10*Zeta[5] + (Pi^2/6)*Zeta[3], 10, 104] // First
%o A256988 (PARI) 10*zeta(5) + zeta(2)*zeta(3) \\ _Michel Marcus_, Apr 14 2015
%Y A256988 Cf. A002117, A013661, A013663, A152648, A152651, A238181, A244667, A256987.
%K A256988 nonn,cons,easy
%O A256988 2,2
%A A256988 _Jean-François Alcover_, Apr 14 2015