|
|
Bernoulli numbers and sqrt(1)+sqrt(2)+sqrt(3) + ... sqrt(1000)
Posted:
Feb 16, 2013 1:42 AM
|
|
The Bernoulli numbers can be used to compute for example 1^10 + 2^10 + ... + 1000^10 .
Jakob Bernoulli wrote around 1700-1713 that he had computed the sum of the 10th powers of the integers 1 through 1000, with the result: 91409924241424243424241924242500
in less than "one half of a quarter hour" ...
Suppose we change the exponent from 10 to 1/2, so the sum is then: sqrt(1) + sqrt(2) + ... sqrt(1000).
Or, more generally, sqrt(1) + sqrt(2) + ... sqrt(N) , N some largish positive integer.
Can Bernoulli numbers or some generalization be used to compute that efficiently and accurately?
My first thought would be that the Euler-MacLaurin summation method might be applicable.
Above, if k^a is the k'th term, a = 1/2 . There's also a= -1 that leads to partial sums of the harmonic series.
David Bernier
-- dracut:/# lvm vgcfgrestore File descriptor 9 (/.console_lock) leaked on lvm invocation. Parent PID 993: sh Please specify a *single* volume group to restore.
|
|