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 A345204 #8 Jan 30 2025 15:50:41
%S A345204 3,6,8,5,7,5,7,4,5,3,2,9,5,7,6,4,1,1,2,7,5,4,0,4,9,5,3,6,4,9,5,9,6,8,
%T A345204 8,8,2,6,7,9,1,9,8,7,1,8,2,4,5,5,9,7,7,1,0,0,9,3,9,4,0,2,2,7,3,6,9,3,
%U A345204 4,3,8,0,8,5,8,8,7,1,3,7,4,5,5,6,1,6,7
%N A345204 Decimal expansion of 5/4 + Pi^2/8 + zeta(3).
%H A345204 Ovidiu Furdui, <a href="http://www.jstor.org/stable/10.4169/math.mag.84.5.371">Series Involving Products of Two Harmonic Numbers</a>, Mathematics Magazine, Vol. 84, No. 5 (2011), pp. 371-377.
%F A345204 Equals Sum_{k>=1} H(k)*H(k+2)/(k*(k+2)), where H(k) = A001008(k)/A002805(k) is the k-th harmonic number (Furdui, 2011).
%F A345204 Equals 5/4 + A111003 + A002117.
%e A345204 3.68575745329576411275404953649596888267919871824559...
%t A345204 RealDigits[5/4 + Pi^2/8 + Zeta[3], 10, 100][[1]]
%o A345204 (PARI) 5/4 + Pi^2/8 + zeta(3) \\ _Stefano Spezia_, Jan 30 2025
%Y A345204 Cf. A001008, A002117, A002805, A111003, A218505, A345203.
%K A345204 nonn,cons
%O A345204 1,1
%A A345204 _Amiram Eldar_, Jun 10 2021