

A239383


Decimal expansion of the probability of a normalerror variable exceeding the mean by more than two standard deviations.


7



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

1,1


COMMENTS

The probability P{(xm)/s > 2} for a normally distributed random variable x with mean m and standard deviation s. In experimental sciences (hypothesis testing), a measured excursion exceeding background "noise" by more than two standard deviations is considered mildly significant if corroborated by additional indications.


LINKS

Stanislav Sykora, Table of n, a(n) for n = 1..1999
Wikipedia, Normal distribution


FORMULA

P{(xm)/s > 2} = P{(xm)/s < 2} = 0.5*erfc(2/sqrt(2)) = erfc(sqrt(2))/2, with erfc(x) being the complementary error function.


EXAMPLE

0.0227501319481792072002826371665334374717762237016784339836660...


PROG

(PARI) n=2; a=0.5*erfc(n/sqrt(2)) \\ Use sufficient realprecision


CROSSREFS

Cf. P{(xm)/s>n}: A239382 (n=1), A239384 (n=3), A239385 (n=4), A239386 (n=5), A239387 (n=6).
Sequence in context: A277199 A116077 A074144 * A011146 A241370 A197735
Adjacent sequences: A239380 A239381 A239382 * A239384 A239385 A239386


KEYWORD

nonn,cons


AUTHOR

Stanislav Sykora, Mar 17 2014


STATUS

approved



