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%I #22 Aug 06 2020 05:10:53
%S 6,2,1,4,4,9,6,2,4,2,3,5,8,1,3,3,5,7,6,3,9,2,6,5,7,2,8,2,1,5,3,3,9,3,
%T 2,3,8,9,3,1,6,4,6,7,6,9,1,9,7,0,5,4,1,6,9,4,7,9,7,5,5,3,1,6,4,1,9,3,
%U 0,5,6,1,6,2,1,3,7,4,5,2,9,8,7,7,7,5,1,9,2,3,9,0,3,6,6,7,4,5,0,7
%N Decimal expansion of Integral_{x=0..Infinity} exp(-x)/(1+x^2) dx.
%H S. R. Finch, <a href="http://arxiv.org/abs/2001.00578">Errata and addenda to Mathematical Constants, p.48.</a>
%F Equals (Pi/2)*cos(1)+cosIntegral(1)*sin(1)-cos(1)*sinIntegral(1).
%F Also equals Integral_{x=0..1} 1/(1+log(x)^2) dx.
%F Equals Integral_{x=0..Pi/2} exp(-tan(x)) dx. - _Amiram Eldar_, Aug 06 2020
%e 0.621449624235813357639265728215339323893164676919705416947975531641930561621...
%t (Pi/2)*Cos[1] + CosIntegral[1]*Sin[1] - Cos[1]*SinIntegral[1] // RealDigits[#, 10, 100]& // First
%K nonn,cons,easy
%O 0,1
%A _Jean-François Alcover_, Apr 09 2013
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