A332628 Decimal expansion of arclength between inflection points of standard normal density function.

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

Offset

1,1

Comments

The inflection points are (-1,1) and (1,1), corresponding to one standard deviation.

Links

Table of n, a(n) for n=1..86.

Example

arclength = 2.02982818143922696710333051626691663409401269956...

Mathematica

s = Integrate[Sqrt[1 + (E^-x^2 x^2)/(2 Pi)], {x, -1, 1}]
r = N[s, 200]
RealDigits[r][[1]]

Prog

(PARI) intnum(x=-1, 1, sqrt(1+exp(-x^2)*x^2/(2*Pi))) \\ Michel Marcus, May 13 2020

Crossrefs

Cf. A333205.

Sequence in context: A137302 A324305 A265607 * A091518 A096734 A220234

Adjacent sequences: A332625 A332626 A332627 * A332629 A332630 A332631

Keyword

nonn,cons,easy

Author

Clark Kimberling, May 13 2020

Status

approved