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A289091
Decimal expansion of (E(|x|^5))^(1/5), with x being a normally distributed random variable.
4
1, 4, 4, 8, 7, 9, 1, 9, 0, 1, 5, 4, 9, 3, 0, 5, 2, 8, 5, 2, 5, 3, 5, 4, 6, 5, 9, 8, 8, 1, 2, 8, 1, 0, 5, 8, 8, 2, 1, 3, 4, 0, 1, 0, 3, 9, 3, 5, 1, 9, 6, 7, 8, 0, 7, 2, 9, 5, 0, 3, 0, 5, 8, 0, 1, 5, 5, 4, 3, 6, 2, 8, 4, 7, 7, 4, 2, 7, 2, 8, 1, 2, 0, 5, 4, 2, 7, 4, 0, 2, 8, 1, 2, 4, 3, 6, 3, 3, 8, 6, 9, 7, 4, 9, 6
OFFSET
1,2
COMMENTS
The 5th root r(5) of the expected value E(|x|^5) for a normal distribution with zero mean and standard deviation 1. See A289090 for more details.
LINKS
FORMULA
Equals r(5), where r(p) = ((p-1)!!*sqrt(2/Pi))^(1/p).
Equals (8*A076668)^(1/5).
EXAMPLE
1.44879190154930528525354659881281058821340103935196780729503058015...
MATHEMATICA
RealDigits[(8*Sqrt[2/Pi])^(1/5), 10, 120][[1]] (* Amiram Eldar, Mar 22 2026 *)
PROG
(PARI) \\ General code, for any p > 0:
r(p) = (sqrt(2/Pi)^(p%2)*prod(k=0, (p-2)\2, p-1-2*k))^(1/p);
a = r(5) \\ Present instance
CROSSREFS
Cf. A060294, A076668 (p=1), A289090 (p=3), A011002 (p=4), A011350 (p=6).
Sequence in context: A110648 A390378 A198936 * A019674 A264606 A388438
KEYWORD
nonn,cons
AUTHOR
Stanislav Sykora, Jul 26 2017
STATUS
approved