A247445 Decimal expansion of the negative derivative of Dawson integral at its inflection points.

2, 8, 4, 7, 4, 9, 4, 3, 9, 6, 5, 6, 8, 4, 6, 4, 8, 2, 5, 2, 2, 0, 3, 1, 5, 7, 4, 4, 6, 7, 7, 3, 4, 1, 7, 4, 5, 4, 6, 6, 2, 5, 5, 2, 7, 7, 0, 6, 2, 8, 4, 7, 4, 1, 6, 8, 7, 6, 0, 7, 5, 9, 5, 1, 7, 0, 2, 6, 8, 3, 1, 7, 3, 2, 0, 4, 7, 8, 4, 5, 8, 6, 3, 7, 3, 7, 5, 4, 5, 8, 1, 7, 9, 4, 6, 3, 4, 2, 4, 1, 2, 4, 9, 7, 1

Offset

0,1

Links

Stanislav Sykora, Table of n, a(n) for n = 0..2000

Eric Weisstein's World of Mathematics, Dawson's Integral

Wikipedia, Dawson function

Formula

Equals 1/(2*xinfl^2-1) = A245262/xinfl, where xinfl=A133843.

Example

0.284749439656846482522031574467734174546625527706284741687607595170...

Prog

(PARI) Erfi(z) = -I*(1.0-erfc(I*z));
Dawson(z) = 0.5*sqrt(Pi)*exp(-z*z)*Erfi(z); \\ same as F(x)=D_+(x)
DDawson(z) = 1.0 - 2*z*Dawson(z); \\ 1st derivative of the above
D2Dawson(z) = -2.0*(z + (1.0-2.0*z*z)*Dawson(z)); \\ 2nd derivative
xinfl = solve(z=1.0, 2.0, real(D2Dawson(z)));
x = -DDawson(xinfl);

Crossrefs

Cf. A133841, A133842, A133843, A243433, A245262.

Sequence in context: A347213 A054530 A253883 * A151928 A365478 A271836

Adjacent sequences: A247442 A247443 A247444 * A247446 A247447 A247448

Keyword

nonn,cons

Author

Stanislav Sykora, Sep 17 2014

Status

approved