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 A386733 #7 Aug 01 2025 11:08:40
%S A386733 5,6,3,8,2,7,3,2,7,6,9,5,7,7,7,4,0,0,5,9,8,2,5,6,6,5,9,5,9,3,3,4,0,5,
%T A386733 4,1,5,4,1,5,2,5,3,1,8,1,1,7,1,1,1,2,8,9,3,7,3,5,8,0,9,0,4,3,0,1,7,8,
%U A386733 3,5,0,8,7,3,7,7,8,8,9,9,4,2,9,4,9,1,2,2,0,3,6,8,2,9,5,8,0,2,2,4,3,2,0,0,0,8
%N A386733 Decimal expansion of Integral_{x=0..1} Integral_{y=0..1} {1/(x+y)} dx dy, where {} denotes fractional part.
%H A386733 Ovidui Furdui, <a href="https://doi.org/10.35834/2004/1602129">Problem 150</a>, Problems, Missouri J. Math. Sci., Vol. 16, No. 2 (2004), p. 130; Huizeng Qin, <a href="https://doi.org/10.35834/2005/1703196">Solution to Problem 150</a>, ibid., Vol. 17, No. 3 (2005), pp. 197-199.
%H A386733 Ovidiu Furdui, <a href="https://doi.org/10.18514/MMN.2016.748">Multiple Fractional Part Integrals and Euler's Constant</a>, Miskolc Mathematical Notes, Vol. 17, No. 1 (2016), pp. 255-266.
%F A386733 Equals 2*log(2) - Pi^2/12 = A016627 - A072691.
%e A386733 0.56382732769577740059825665959334054154152531811711...
%t A386733 RealDigits[2*Log[2] - Pi^2/12, 10, 120][[1]]
%o A386733 (PARI) 2*log(2) - zeta(2)/2
%Y A386733 Cf. A016627, A072691, A153810, A345208, A386734, A386735.
%K A386733 nonn,cons
%O A386733 0,1
%A A386733 _Amiram Eldar_, Aug 01 2025