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Subject: Re: Quick n-th Root of BigInteger
Date: Fri, 08 Jun 2012 13:55:37 -0700
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On 6/8/2012 1:36 PM, Jan Burse wrote:
> Gene Wirchenko schrieb:
>> On Fri, 08 Jun 2012 21:03:56 +0200, Jan Burse <janburse@fastmail.fm>
>> wrote:
>>
>>> Dear All,
>>>
>>> What is your favorite algorithm to compute the n-th Square of
>>> a BigInteger, i.e.
>>>
>>> Given: x, n
>>> Compute: y = max { z | z^n =< x }
>>
>> Do you mean the integer part of the nth *root* of z given integer
>> x and n?

> Sorry, yes root, and z integer.


Positive integers?  Do you want the complex roots too? ;-)  You ask big 
questions Jan, but I think you need to ask them a little more thoughtfully.

I'm confused about the max, the z |, and the  =< x.  Care to explain 
what those signify in your question?  If you want something besides the 
real, positive nth root of A=z^n, what do you want?  I think "nth root 
of A" is the correct phrasing, which leads to the wonder what the other 
mathematical verbiage signifies.