Re: Try to calculate

From: Tom St Denis (tomstdenis_at_iahu.ca)
Date: 05/29/03 

Date: Thu, 29 May 2003 03:16:49 GMT

????? wrote:
> I tried to calculate the number of primes of 512 bit long. Hope
> someone may verify the result.
> According to Gauss's prime number theorem, the number of primes less
> than n should be n/ln(n).
> 2^512/ln(2^512) - 2^511/ln(2^511) = ?
> Using my PC's Calculator got 1.885305082130081660668523138413e+151,
> Really big. Somthing you cannot store in any computer.

Um? yea, you can't store 2^503 or so primes in memory, but yes you can
store the number 2^503 in memory. For the record 2^503 ==

26187124863169134960105517574620793217733136368344518315866330944769\
07037123739643906616073860723325720709347302048056807373805236708314\
4426628220715008

[Not particularly hard to calculate :-), you can do it by hand with
about 8 squarings and 7 multiplications in under an hour or so].

Tom

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