## psp(5) to 10^12

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• 1. a file of Fermat psp(5)S up to 10^12 or higher?? Posted by: hanrahan398 hanrahan398@yahoo.co.uk hanrahan398 Date: Fri Jun 23, 2006 12:46 PM (PDT) I d be
Message 1 of 1 , Jun 24, 2006
1. a file of Fermat psp(5)S up to 10^12 or higher??
Posted by: "hanrahan398" hanrahan398@... hanrahan398
Date: Fri Jun 23, 2006 12:46 PM (PDT)

I'd be grateful if someone could direct my attention to where I might
get hold of a file of psp(5)S up to 10^12 or higher.

Many thanks!

Michael

******

>From web site

http://www.cs.xu.edu/math/math302/04f/hints.html

I found this note.

6.1.4

It is actually not feasible to "construct a table that contains all the
numbers less than or equal to 10^9
that are pseudoprimes to bases 2, 3, and 5." There are just too many
numbers to check.

When I implemented the Maple code I wrote for this problem, it took ten
minutes for the machine to find the
appropriate list of numbers up to 2 million. At this rate it should take
5000 minutes = 83 hours to build the
entire table of psp(2,3,5)S up to one billion!!! (I am calling a number
psp(2,3,5) if it is simultaneously a
psp(2), psp(3) and psp(5).) What I suggest you do instead is to build your
code so that it checks an interval
of just 1000 numbers in order to search for psp(2,3,5) values, and then
adjust the endpoints of the interval to
determine a complete list of psp(2,3,5) values near the numbers whose
primality we are testing

Kermit < kermit@... >
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