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%I #16 Sep 18 2014 04:54:14
%S 9,2,4,1,3,8,8,7,3,0,0,4,5,9,1,7,6,7,0,1,2,8,2,3,2,7,1,5,0,4,3,4,5,9,
%T 7,5,6,9,6,2,9,1,5,5,9,9,3,5,1,6,3,9,1,7,5,9,7,8,1,0,5,2,9,8,4,9,7,5,
%U 9,5,4,0,1,6,2,1,9,3,8,8,1,6,8,5,6,2,7,7,7,1,2,1,4,5,8,4,7,3,8,5,5,6,9,4,8
%N Decimal expansion of the position of the positive real maximum of Dawson's integral D_+(x).
%H Stanislav Sykora, <a href="/A133841/b133841.txt">Table of n, a(n) for n = 0..2000</a>
%H Eric Weisstein's World of Mathematics, <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 1/(2*A133842).
%e 0.92413887300459176701...
%t DawsonF[x_] := Sqrt[Pi]*Erfi[x]/(2*Exp[x^2]); x0 = x /. FindRoot[ DawsonF'[x], {x, 1}, WorkingPrecision -> 110]; RealDigits[x0][[1]][[1 ;; 105]] (* _Jean-François Alcover_, Oct 26 2012, after _Eric W. Weisstein_ *)
%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)
%o DDawson(z) = 1.0 - 2*z*Dawson(z); \\ Derivative of the above
%o x = solve(z=0.1,2.0,real(DDawson(z))) \\ _Stanislav Sykora_, Sep 17 2014
%Y Cf. A133842, A133843, A243433.
%K nonn,cons
%O 0,1
%A _Eric W. Weisstein_, Sep 26 2007
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