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Forum: Homework Help 2021-11-27, 16:32
Replies: 22
Views: 3,833
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: 234
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: 234
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: 3,833
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: 234
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: 44,010
Posted By charybdis
Thank you for organising! Hope the linear algebra...

Thank you for organising! Hope the linear algebra goes smoothly.
Forum: Number Theory Discussion Group 2021-11-22, 21:15
Replies: 7
Views: 370
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: 44,010
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: 44,010
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: 44,010
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: 44,010
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: 44,010
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: 44,010
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: 44,010
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: 44,010
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: 44,010
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
Views: 162,918
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: 44,010
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: 44,010
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: 44,010
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: 44,010
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: 773
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: 44,010
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: 44,010
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.
Forum: Cunningham Tables 2021-11-09, 12:04
Replies: 315
Views: 44,010
Posted By charybdis
Well well... I tried -bkthresh1 and discovered...

Well well... I tried -bkthresh1 and discovered that the latest CADO has a bug! It was probably introduced during the recent improvements to las. I'll report it to the CADO team later.

Using an...
Showing results 1 to 25 of 541

 
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