Paul Underwood on Fri, 27 Sep 2019 15:03:50 +0200

 qfbsolve (and ispseudoprime)

• To: pari-users@pari.math.u-bordeaux.fr
• Subject: qfbsolve (and ispseudoprime)
• From: "Paul Underwood" <paulunderwood@mindless.com>
• Date: Fri, 27 Sep 2019 14:58:43 +0200
• Delivery-date: Fri, 27 Sep 2019 15:03:51 +0200
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```It is a pity that the function qfbsolve is much slower in 2.12 alpha where it solves for composite n too.

For example:

gettime();k=198;n=2^p-3;if(qfbsolve(Qfb(1,0,1),n),print([k,gettime()]))

overflows the default stack whereas it gives an almost instantaneous answer with version 2.11 and version 2.9.

Also, qfbsolve(Qfb(1,0,1),n) *was* quicker than ispseudoprime for positive integers of the form 4*K+1,

Best

Paul

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