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%I #16 Sep 18 2014 04:53:20
%S 4,2,7,6,8,6,6,1,6,0,1,7,9,2,8,7,9,7,4,0,6,7,5,5,6,4,2,1,1,2,6,9,5,1,
%T 9,1,9,3,6,2,4,5,5,3,4,5,2,7,8,1,9,5,8,8,7,6,3,6,0,6,0,9,7,1,9,0,3,5,
%U 2,0,5,5,9,0,8,8,3,4,0,0,3,6,9,6,4,3,9,6,9,8,3,4,2,8,4,5,8,8,9,3,4,9,1,6
%N Decimal expansion of Dawson's integral at the inflection point.
%D Steven R. Finch, Mathematical Constants, Cambridge University Press, 2003, Section 8.9 Hyperbolic volume constants, p. 512.
%H Stanislav Sykora, <a href="/A245262/b245262.txt">Table of n, a(n) for n = 0..2000</a>
%H Eric Weisstein's MathWorld, <a href="http://mathworld.wolfram.com/DawsonsIntegral.html">Dawson's Integral</a>
%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Dawson_function">Dawson function</a>
%F Equals xinfl/(2*xinfl^2-1), xinfl = A133843. - _Stanislav Sykora_, Sep 17 2014
%e 0.427686616017928797406755642112695191936245534527819588763606097190352...
%t digits = 104; DawsonF[x_] := Sqrt[Pi]*Erfi[x]/(2*Exp[x^2]); xi = x /. FindRoot[DawsonF''[x], {x, 3/2}, WorkingPrecision -> digits + 10]; RealDigits[DawsonF[xi], 10, digits] // First
%o (PARI) Erfi(z) = -I*(1.0-erfc(I*z));
%o Dawson(z) = 0.5*sqrt(Pi)*exp(-z*z)*Erfi(z); \\ same as F(x)=D_+(x) D2Dawson(z) = -2.0*(z + (1.0-2.0*z*z)*Dawson(z)); \\ 2nd derivative
%o xinfl = solve(z=1.0, 2.0, real(D2Dawson(z)));
%o x = Dawson(xinfl) \\ _Stanislav Sykora_, Sep 17 2014
%Y Cf. A133841, A133842, A133843, A247445.
%K nonn,cons
%O 0,1
%A _Jean-François Alcover_, Jul 15 2014
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