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%I #11 Sep 24 2015 18:40:57
%S 1,3,8,0,3,8,8,4,4,7,0,4,3,1,4,2,9,7,4,7,7,3,4,1,5,2,4,6,7,2,5,5,9,1,
%T 2,7,4,2,7,0,7,7,2,4,6,5,5,6,2,2,1,0,7,9,8,4,5,0,2,4,6,8,5,0,7,1,5,7,
%U 4,8,2,6,5,6,1,0,4,6,6,3,9,1,8,9,2,3,8,0,6,4,3,4,3,3,8,4,1,2,5,6,0,5,6,1,2
%N Decimal expansion of sqrt(Pi/sqrt(e)).
%H Stanislav Sykora, <a href="/A257530/b257530.txt">Table of n, a(n) for n = 1..2000</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CosineIntegral.html">Cosine Integral</a>, Eq.20
%F Equals integral[-inf..+inf](exp(-x^2)*cos(k*x)) = sqrt(Pi/exp(k^2/2)), for k = 1.
%e 1.38038844704314297477341524672559127427077246556221079845024685...
%t RealDigits[N[Sqrt[Pi/Sqrt@ E], 120]] (* _Michael De Vlieger_, Apr 30 2015 *)
%o (PARI) a = sqrt(Pi/sqrt(exp(1)))
%Y Cf. A000796, A001113, A096414.
%K nonn,cons
%O 1,2
%A _Stanislav Sykora_, Apr 28 2015