Values of Dawson's integral $F(x)$
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Numbers
$x$ 
$F(x)$
0:
0
$x_{\mathrm{max}}$:
0.5410442246351816984727593302414771863906046768268258874563542169084205587981469753143919102132277710
comment: The unique positive maximum; its argument is defined in (6).
1:
0.5380795069127684191363874204075567547919750017539333188752190980025665033305271062972608615027430809
1/2:
0.4244363835020222959340423524896695710964294773596920381513396966332451547595919476167712012847861222
3/2:
0.4282490710853986254771901051517453449916012788166562318895886286085699329393240293426251681961068270
2:
0.3013403889237919660346644392864226952119153384042494376596630521374710864689484069634795676468781777
3:
0.1782710306105582873425994922405126302291599294376416000329048446501844478791472243676317105043070870
$\sqrt{2}$:
0.4525399074037224703440073960862168590994043939869132566319867175401897197190716042836755357182956770
$\sqrt{3}$:
0.3640970973281268535201736302281541036186636118335582645637441932613370990680883368529600771287271763
$\sqrt{5}$:
0.2587244442126722504277125796253789848441501551529697369218405876350847040585700381858031651270030823
$\sqrt{6}$:
0.2290847511404287300178883714920244752984561094803261033765120681808762659032923886945267720806379598
$\sqrt{7}$:
0.2075560539194269251798062923699606488496918793586078880793136506274682542715528570770555074078032351
$\sqrt{8}$:
0.1911990543773802715037427059671847231475292165984662553674280137654307104423559792190600579391323814
Definition
Dawson's integral is $F(x)=e^{-x^2}\int_0^x e^{t^2}\,\mathrm{d}t$ [2], the function written $D_+$. This table gives its values at selected nonnegative real arguments.
Parameters
$x$
—   argument ($x\geq0$)
Formulas
(1)
Dawson's integral is $F(x)=e^{-x^2}\int_0^x e^{t^2}\,\mathrm{d}t=(\sqrt{\pi}/2)e^{-x^2}\operatorname{erfi}(x)$ [2].
(2)
The functions $\operatorname{erf}$, $\operatorname{erfi}$, $F$, $S$ and $C$ are odd, and $\operatorname{erfc}(-x)=2-\operatorname{erfc}(x)$.
Comments
(3)
Dawson's integral $F(x)$ is the function written $D_+(x)$ in [2]. The variant $D_-(x)=e^{x^2}\int_0^x e^{-t^2}\,\mathrm{d}t$ is not stored; it is $(\sqrt{\pi}/2)e^{x^2}\operatorname{erf}(x)$.
(4)
Negative arguments are not listed separately. Values at negative arguments follow from (2).
(5)
At $x=0$ the value is exact, $F(0)=0$, and is stored as the integer rather than as a hundred places of one.
(6)
The damped quadratic-coefficient integral $\int_0^1 e^{-a(1-t^2)}\,dt=F(\sqrt a)/\sqrt a$ selects the square-root arguments. The coefficients $1\leq a\leq9$ form a short exploratory reference family; the finite cutoff is not intrinsic. The direct endpoints $1/2$ and $3/2$ complement the unit anchor in the subunit and crossover regimes. Negative arguments follow by oddness. These choices do not assert a published application for every coefficient. Definitions and the Dawson/error-function relation are in [9]. The retained maximal height is $F(x_{\mathrm{max}})$, where $x_{\mathrm{max}}\in(1/2,1)$ is the unique positive root of $1-2xF(x)=0$. Since $F^{\prime}=1-2xF$ and $F^{\prime\prime}=-2F<0$ at each positive stationary point, every such point is a strict downward derivative crossing, so there is only one.
Programs
(P1)
Sage
import numberdb.sage as numberdb
from sage.rings.rational_field import QQ
from sage.rings.real_arb import RealBallField

field = RealBallField(numberdb.bits(100, losing=64))
x = field(QQ(1))
field.pi().sqrt() * (-x * x).exp() * x.erfi() / field(2)
(P2)
Python
import mpmath as mp

mp.mp.dps = 100
argument = mp.mpf(1)
mp.sqrt(mp.pi) * mp.exp(-argument**2) * mp.erfi(argument) / 2
Links
Similar tables
Values of the error function $\operatorname{erf}(x)$ —   the same Gaussian integrand, with $e^{+t^2}$
Values of the complementary error function $\operatorname{erfc}(x)$ —   another member of the error-function family
Values of the imaginary error function $\operatorname{erfi}(x)$ —   $F(x)=(\sqrt{\pi}/2)e^{-x^2}\operatorname{erfi}(x)$
Values of the Fresnel sine integral $S(x)$ —   another member of the error-function family
Values of the Fresnel cosine integral $C(x)$ —   another member of the error-function family
Values of the exponential integral —   stores $\operatorname{Ei}(x)$ and $E_1(x)$, with exponential kernels $e^t/t$ and $e^{-t}/t$ rather than the Gaussian kernel $e^{-t^2}$
Values of the sine integral $\operatorname{Si}(x)$ —   stores $\operatorname{Si}(x)=\int_0^x\sin(t)/t\,\mathrm{d}t$, with linear phase in place of the Fresnel quadratic phase
Values of the cosine integral $\operatorname{Ci}(x)$ —   stores $\operatorname{Ci}(x)=\gamma+\log x+\int_0^x(\cos(t)-1)/t\,\mathrm{d}t$, with linear phase in place of the Fresnel quadratic phase
Values of the hyperbolic sine integral $\operatorname{Shi}(x)$ —   stores $\operatorname{Shi}(x)=\int_0^x\sinh(t)/t\,\mathrm{d}t$ at rational arguments
Values of the hyperbolic cosine integral $\operatorname{Chi}(x)$ —   stores $\operatorname{Chi}(x)=\gamma+\log x+\int_0^x(\cosh(t)-1)/t\,\mathrm{d}t$ at rational arguments
Values of the Gamma function at rational numbers —   contains $\Gamma(1/2)=\sqrt{\pi}$, the normalising constant in $\operatorname{erf}$ and $\operatorname{erfc}$
Data properties
Entries are of type: real number
Table is complete: no (it retains all earlier anchors and covers $x=\sqrt a$ for integers $1\leq a\leq9$, together with $x=1/2,3/2$ and the origin and the unique positive maximal height; the quadratic-coefficient family is a bounded exploratory reference, not a dense argument grid)
How they were obtained:

All retained numeric strings, exact values and row annotations are unchanged. The standalone generate.py, balanced_values.py and selection.json reproduce the entire current selection. Each finite Arb enclosure at 733 bits must fit inside the interval claimed by the written last place; a second run uses 912 bits. New nonexact entries have 100 significant digits.

more

Every new entry has an independent mpmath quadrature, closed-form or inverse-function check at 150 and 200 decimal digits, with a nonzero known-integral control. Arguments are exact rationals or propagated balls from exact expressions; root arguments use strict sign-certified rational brackets. Lambert and saddle roots also pass endpoint sign tests on the written last-place interval. The measurements are in coverage-checks.json. Older attachments are retained for provenance; their previous enumerations are historical, and the active enumeration is selection.json.