OFFSET
1,1
COMMENTS
It appears that a good estimate for the standard deviation of primes below 10^(n+1) is about 10 times the term for 10^n.
Heuristically, if we use a model where each positive integer x has probability approximately 1/log(x) of being prime, we should expect the standard deviation of the primes below N to be approximately N/sqrt(12). - Robert Israel, Sep 23 2014
REFERENCES
John E. Freund, Modern elementary statistics, 5th ed. (Prentice-Hall, 1979), pp. 42-47
EXAMPLE
a(6) = 292821 (rounded from 292820.634) because this is the computed and rounded sample standard deviation of the 78498 primes below 10^6.
MAPLE
seq(round(Statistics:-StandardDeviation(select(isprime, [$2 .. 10^n-1]))), n=1..7); # Robert Israel, Sep 23 2014
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Enoch Haga, Mar 05 2004
EXTENSIONS
a(9)-a(13) from Hiroaki Yamanouchi, Sep 23 2014
STATUS
approved