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 Showing results 1 to 25 of 542 Search took 0.07 seconds. Search: Posts Made By: charybdis
 Forum: Miscellaneous Math 2021-11-28, 12:03 Replies: 419 Views: 39,162 Posted By charybdis Sorry to disappoint you. Robert [Don't... Sorry to disappoint you. Robert [Don't want to start any arguments about whether I could *eventually* be a woman...]
 Forum: Homework Help 2021-11-27, 16:32 Replies: 22 Views: 3,868 Posted By charybdis And we can do this combinatorially too: both are... And we can do this combinatorially too: both are the way of choosing k elements from a set of p elements, where we label one of those k elements as "special". We get k*binomial(p,k) by choosing the...
 Forum: Cunningham Tables 2021-11-27, 14:38 Replies: 5 Views: 256 Posted By charybdis Perhaps. While I didn't see much dropoff up to... Perhaps. While I didn't see much dropoff up to 40M, that doesn't mean there won't be by 400M. I suppose the prudent thing to do would be to run smallish ranges (100k?) at 40M and 400M and compare the...
 Forum: Cunningham Tables 2021-11-27, 02:01 Replies: 5 Views: 256 Posted By charybdis Depends if you set ropteffort very high. With... Depends if you set ropteffort very high. With ropteffort=100 you'll be fine. 200 might potentially need more time on old/slow CPUs. Your adrange is small enough that the length of the...
 Forum: Homework Help 2021-11-26, 18:12 Replies: 22 Views: 3,868 Posted By charybdis It depends what you mean by "reduced". Try... It depends what you mean by "reduced". Try subtracting p from all the factors of the numerator, so p-1 turns into -1, p-2 into -2 etc, and see what that gives you.
 Forum: Cunningham Tables 2021-11-26, 00:56 Replies: 5 Views: 256 Posted By charybdis Polynomial selection for 2,2246M c221 This is one of only two remaining unambiguous GNFS numbers from the 1987 edition of the Cunningham book (base 2 <1200 bits), the other being 2,1109+ c225. Bob Silverman suggested that the forum...
 Forum: Cunningham Tables 2021-11-25, 20:08 Replies: 315 Views: 44,072 Posted By charybdis Thank you for organising! Hope the linear algebra... Thank you for organising! Hope the linear algebra goes smoothly.
 2021-11-22, 21:15 Replies: 7 Views: 375 Posted By charybdis This may be a valid PRP test (i.e. "p is prime"... This may be a valid PRP test (i.e. "p is prime" => "condition holds") for q > 3. But you haven't proved anything in the other direction, namely "condition holds" => "p is prime". Things break down...
 Forum: Cunningham Tables 2021-11-20, 18:57 Replies: 315 Views: 44,072 Posted By charybdis Specifically it's the merge phase that's... Specifically it's the merge phase that's multi-threaded. The rest of filtering is still single-threaded. I remember reading somewhere that subsequent changes to CADO mean that this doesn't...
 Forum: Cunningham Tables 2021-11-20, 16:46 Replies: 315 Views: 44,072 Posted By charybdis The A/I value determines the size of the sieve... The A/I value determines the size of the sieve region, i.e. how hard we search for relations at each special-Q. Higher A values will always have higher yield but worse rels/sec, but if you use too...
 Forum: Cunningham Tables 2021-11-18, 23:39 Replies: 315 Views: 44,072 Posted By charybdis Ah whoops, got these mixed up. Thanks for the... Ah whoops, got these mixed up. Thanks for the correction!
 Forum: Cunningham Tables 2021-11-18, 19:30 Replies: 315 Views: 44,072 Posted By charybdis --bind-to none should only be needed with -np 2.... --bind-to none should only be needed with -np 2. --bind-to socket ought to have the same effect. When there are at least 3 processes OpenMPI will bind to socket by default. I have no clue why it...
 Forum: Cunningham Tables 2021-11-18, 16:43 Replies: 315 Views: 44,072 Posted By charybdis Very good! This confirms that A=30 was the right... Very good! This confirms that A=30 was the right choice. They were PMs, not posts :smile: The answer to these is generally "maybe - give it a try". As long as the matrix remains above...
 Forum: Cunningham Tables 2021-11-18, 12:53 Replies: 315 Views: 44,072 Posted By charybdis You'll probably want to wait at least until a... You'll probably want to wait at least until a matrix can be built with target_density=120; I expect VBCurtis will chime in later with his thoughts. Chances are if you tried TD=120 now you would get...
 Forum: Cunningham Tables 2021-11-18, 11:54 Replies: 315 Views: 44,072 Posted By charybdis My clients - and seemingly everyone else's - were... My clients - and seemingly everyone else's - were unable to connect to the server for 3 hours last night, until about 07:10 your time. The logs show the same "Connection timed out" error as they do...
 Forum: Cunningham Tables 2021-11-17, 20:59 Replies: 315 Views: 44,072 Posted By charybdis Do rankings usually start at 0th place in... Do rankings usually start at 0th place in Germany? :ermm: (nice work again btw)
 Forum: Cunningham Tables 2021-11-17, 13:29 Replies: 315 Views: 44,072 Posted By charybdis Only in Greg's version of msieve, not the... Only in Greg's version of msieve, not the "official" one.
 Forum: NFS@Home 2021-11-17, 12:48 Replies: 1,872 Sticky: BOINC NFS sieving - NFS@Home Views: 162,944 Posted By charybdis If you want something to try this out on, the... If you want something to try this out on, the octic for 2,1180+ (diff. 285) sieves ~3 times faster than the quartic. Hard to do an exact comparison because yield drops off so much faster for the...
 Forum: Cunningham Tables 2021-11-17, 12:35 Replies: 315 Views: 44,072 Posted By charybdis Well I can't say I've ever tried to cat >200k... Well I can't say I've ever tried to cat >200k files at once before :smile: Glad you found a good solution. Of course I should have said "A5 to A0" rather than "A6 to A0" in my previous post. Not...
 Forum: Cunningham Tables 2021-11-17, 11:25 Replies: 315 Views: 44,072 Posted By charybdis I just run cat *.gz >> [msieve directory... I just run cat *.gz >> [msieve directory path]/msieve.dat.gz in the upload directory and then msieve -nc -v -t [threads] in the msieve directory. If you want to avoid creating a completely new...
 Forum: Cunningham Tables 2021-11-16, 18:59 Replies: 315 Views: 44,072 Posted By charybdis Nice work! The jump is from the initial change... Nice work! The jump is from the initial change from strategy 2 to strategy 0. The later change back to strategy 2 had a much smaller effect and is basically impossible to spot.
 Forum: Cunningham Tables 2021-11-15, 23:38 Replies: 315 Views: 44,072 Posted By charybdis What's going on here? Was this something like... What's going on here? Was this something like A=32? I hope it wasn't higher lpbs because then the extra relations would be useless.
 Forum: CADO-NFS 2021-11-11, 22:02 Replies: 18 Views: 779 Posted By charybdis I find that Haswell and Skylake have very similar... I find that Haswell and Skylake have very similar speed/GHz for CADO. Skylake runs about 10% faster than Haswell for ECM. Some of the newer Intel architectures are substantially faster per GHz for...
 Forum: Cunningham Tables 2021-11-09, 23:53 Replies: 315 Views: 44,072 Posted By charybdis Strange. I get 136s with -bkthresh1 3e7 and 108s... Strange. I get 136s with -bkthresh1 3e7 and 108s without. Adding in your -bkmult 1,1l:1.08598,1s:1.30264,2s:1.08933 changes this to 123s with -bkthresh1 and 112s without. I doubt my system is 3 times...
 Forum: Cunningham Tables 2021-11-09, 18:47 Replies: 315 Views: 44,072 Posted By charybdis I tried 1e8, 5e7, 1e7 and 2e6. All were at least... I tried 1e8, 5e7, 1e7 and 2e6. All were at least 20% slower than without -bkthresh1.
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