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 A111922 #11 Feb 16 2025 08:32:58
%S A111922 1,33,2705,86641,54233569,18084523,43438219723,1390063548011,
%T A111922 337834614646673,337850745678737,4946795388123668417,
%U A111922 4946852336050088417,141291773058735555757937,141293528936024618797937
%N A111922 Numerator of x(n) = Sum_{k=1..n} ((odd part of k)/(k^5)).
%C A111922 Denominator of x(n) = A111923(n);
%C A111922 x(n) = a(n)/A111923(n) -> (Pi^4)/93 = 30*zeta(4)/31.
%D A111922 G. Pólya and G. Szegő, Problems and Theorems in Analysis II (Springer 1924, reprinted 1972), Part Eight, Chap. 1, Sect. 6, Problem 50.
%H A111922 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/OddPart.html">Odd Part</a>
%H A111922 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/RiemannZetaFunction.html">Riemann Zeta Function</a>
%e A111922 a(20) = 16405158877294964819100166210727563,
%e A111922 A111923(20) = 15663005949803936428703787909120000:
%e A111922 x(20) = a(20)/A111923(20) = 1.04738..., x(20)*31/30=1.08229....
%Y A111922 Cf. A000265, A013662, A111929, A111918, A111920, A111923.
%K A111922 nonn,frac
%O A111922 1,2
%A A111922 _Reinhard Zumkeller_, Aug 21 2005