Other Factordb Problems

[schickel]

Originally Posted by Stargate38

What's causing the "err" status on certain numbers? It's breaking 9 of the Aliquot sequences. Here's an example (from 270870):

http://factordb.com/index.php?id=1100000000626093582

i think for all the sequences that are broken they are broken as a result of errors like this. If you look, the number is even, but something bombed when the number was inserted and it will not accept factors reported (or anything else). They're a matter for Syd to fix, unfortunately.

[chris2be8]

After clicking Combined N-1/N+1-test for (1205^311-1)/1204, http://factorization.ath.cx/index.ph...00000802222052, I got:

Test finished!
PFGW output:

Primality testing (1205^311-1)/1204 [N-1/N+1, Brillhart-Lehmer-Selfridge]
Running N-1 test using base 2
Running N+1 test using discriminant 11, base 2+sqrt(11)
Calling N-1 BLS with factored part 32.16% and helper 3.06% (99.56% proof) Proof incomplete rerun with -x31906
(1205^311-1)/1204 is Fermat and Lucas PRP! (0.1456s+0.0001s)

But it still shows as composite.

N-1 shows 32.177% factored and N+1 shows 3.088% factored so it should be able to prove it prime.

Chris

[paulunderwood]

What are the contents of the "helper" file?

[axn]

Originally Posted by chris2be8

N-1 shows 32.177% factored and N+1 shows 3.088% factored so it should be able to prove it prime.
Chris

32.177*3+3.088 = 99.619 is short of 100% needed for the proof. You need another 956 * (100.-99.619)% = 4 digits more of factors
EDIT:- Actually it says right there what needs to be done.

Calling N-1 BLS with factored part 32.16% and helper 3.06% (99.56% proof) Proof incomplete rerun with -x31906

[chris2be8]

Originally Posted by paulunderwood

What are the contents of the "helper" file?

2
3
5
11
31
41
67
241
311
373
1117
5333
19841
65581
94201
14454014741
15310978493
51466530341
238577955233
3623008528351
16882076013511
571942065602617231
136579192917993601851013
304886788909843277271659233981
24093066218972488602853684540493150881377214116399041593
2707569731064359648574014702758332334432814852672149601505089496049710691427
23
23008944777617
144698299486159

But does that help?

Chris

[chris2be8]

Originally Posted by axn

32.177*3+3.088 = 99.619 is short of 100% needed for the proof. You need another 956 * (100.-99.619)% = 4 digits more of factors
EDIT:- Actually it says right there what needs to be done.

When I first saw the number I ran some ECM against the composite factors of N-1 and N+1. And found a small factor of N+1. But that's probably used up my quota of luck.

The interesting point is that factordb provides a proof button, even thought there aren't quite enough known factors to prove the number prime.

Chris

[paulunderwood]

./pfgw64 -V -i -tc  -q"(1205^311-1)/1204" -hahelper.txt -x31906 
PFGW Version 3.7.7.64BIT.20130722.x86_Dev [GWNUM 27.11]


CPU Information (From Woltman v26 library code)
Intel(R) Core(TM) i7-4770K CPU @ 3.50GHz
CPU speed: 3257.16 MHz, 4 cores
CPU features: RDTSC, CMOV, Prefetch, MMX, SSE, SSE2, SSE4.1, SSE4.2
L1 cache size: 32 KB
L2 cache size: 256 KB, L3 cache size: 8 MB
L1 cache line size: 64 bytes
L2 cache line size: 64 bytes
TLBS: 64
                                    
Primality testing (1205^311-1)/1204 [N-1/N+1, Brillhart-Lehmer-Selfridge]                                    
Reading factors from helper file ahelper.txt
Running N-1 test using base 2                                                  
Generic modular reduction using generic reduction AVX FFT length 320 on A 3173-bit number                                    
Running N+1 test using discriminant 11, base 2+sqrt(11)                                    
Generic modular reduction using generic reduction AVX FFT length 320 on A 3173-bit number                                    
(1205^311-1)/1204 is prime! (0.1615s+0.0005s)

-x Additional Square Free Testing
This will make PFGW try to prove a prime with a tiny bit less then
33.3% factorisation of N-1 or N+1.
Default value is -x100

[axn]

Originally Posted by chris2be8

The interesting point is that factordb provides a proof button, even thought there aren't quite enough known factors to prove the number prime.

Yes. Factordb (incorrectly) calculates it as 3*(m+p) instead of 3*larger(m,p)+smaller(m,p).

[jyb]

Is anybody able to use factordb.com at all right now? It does nothing but show me the "maximum parallel requests" page, even trying to load its home page.

Does it need a kick?

[schickel]

Originally Posted by jyb

Is anybody able to use factordb.com at all right now? It does nothing but show me the "maximum parallel requests" page, even trying to load its home page.

Does it need a kick?

Syd may be doing maintenance. This is what I get:

Could not connect to database

[Stargate38]

Could not connect to database.

I'm getting the same error. At first I was unable to get the Aliquot sequence for 276 to come up, unless I chose "Show last". When I chose "Last 20" or "Show all", I couldn't get it to come up, even after 20 minutes. After than I somehow ended up at the "maximum parallel requests" page, then exceeded my 2500 second CPU time quota (I don't know how). I hope it gets fixed, because it's holding back Yafu@Home and any other sites that are dependent on the db.