Karim Belabas on Sat, 21 Aug 2010 20:12:18 +0200 |
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Re: Improvement to BPSW_isprime_small |
Thanks for notifying us. I have modified BSPW_isprime_small() accordingly [ 'testing' branch only ]. Cheers, K.B. * Charles Greathouse [2010-08-18 20:26]: > Last year Jan Feitsma (with Will Galway, I believe) completed a tour > de force: calculating all the 2-pseudoprimes up to 2^64. He has only > recently announced this result; you can find the list here: > http://www.cecm.sfu.ca/Pseudoprimes/index-2-to-64.html > > In October 2009 Jeff Gilchrist and David Cleaver verified this result > with Jan's algorithm and independently-written code to guard against > bugs. Further, Jeff checked that there were no BPSW pseudoprimes in > that range using Thomas R. Nicely's BPSW code: > http://www.trnicely.net/misc/bpsw.html > > I checked this result with Pari's ispseudoprime, duplicating Jeff's results. > > As a result, the limits in BPSW_isprime_small can be raised > substantially. This would dramatically improve the speed of checking > primes p in (10^15, 2^64) ~ (1e15, 1.8e19). > > Charles Greathouse > Analyst/Programmer > Case Western Reserve University > > P.S. I apologize in advance to anyone involved in this effort that I > failed to mention; with a project this size it's almost inevitable. -- Karim Belabas, IMB (UMR 5251) Tel: (+33) (0)5 40 00 26 17 Universite Bordeaux 1 Fax: (+33) (0)5 40 00 69 50 351, cours de la Liberation http://www.math.u-bordeaux1.fr/~belabas/ F-33405 Talence (France) http://pari.math.u-bordeaux1.fr/ [PARI/GP] `