cp's OEIS Frontend

A087654 Decimal expansion of D(1) where D(x) is the Dawson function.

%I A087654 #31 Feb 16 2025 08:32:51
%S A087654 5,3,8,0,7,9,5,0,6,9,1,2,7,6,8,4,1,9,1,3,6,3,8,7,4,2,0,4,0,7,5,5,6,7,
%T A087654 5,4,7,9,1,9,7,5,0,0,1,7,5,3,9,3,3,3,1,8,8,7,5,2,1,9,0,9,8,0,0,2,5,6,
%U A087654 6,5,0,3,3,3,0,5,2,7,1,0,6,2,9,7,2,6,0,8,6,1,5,0,2,7,4,3,0,8,0,9,3,8,8,9
%N A087654 Decimal expansion of D(1) where D(x) is the Dawson function.
%D A087654 Jerome Spanier and Keith B. Oldham, "Atlas of Functions", Hemisphere Publishing Corp., 1987, chapter 42, page 407.
%H A087654 G. C. Greubel, <a href="/A087654/b087654.txt">Table of n, a(n) for n = 0..5000</a>
%H A087654 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/DawsonsIntegral.html">Dawson's Integral</a>.
%F A087654 D(1) = (1/e)*Integral_{t=0..1} exp(t^2) dt.
%F A087654 Equals Integral_{x=0..oo} e^(-x^2) sin(2x) dx = 1F1(1;3/2;-1). - _R. J. Mathar_, Jul 10 2024
%F A087654 Equals A099288 * sqrt(Pi)/(2e) = A099288 *A019704 * A068985. - _R. J. Mathar_, Jul 10 2024
%e A087654 0.5380795069127684191363874204075567547919750017539...
%t A087654 RealDigits[ N[ Sqrt[Pi]*Erfi[1]/(2*E), 105]][[1]] (* _Jean-François Alcover_, Nov 08 2012 *)
%t A087654 RealDigits[DawsonF[1], 10, 120][[1]] (* _Amiram Eldar_, Jun 25 2023 *)
%o A087654 (PARI) intnum(t=0, 1, exp(t^2))/exp(1) \\ _Michel Marcus_, Feb 28 2023
%K A087654 cons,nonn
%O A087654 0,1
%A A087654 _Benoit Cloitre_, Sep 25 2003