AS3366:i2103 C158
 

If there is still interest in this thread yet another Aliquot Sequence has reached NFS This is a C158 from Seq 3366.

Last term [URL="http://factordb.com/sequences.php?se=1&aq=3366&action=last"]here[/URL].

Composite [URL="http://factordb.com/index.php?id=1100000000638060674"]here[/URL].

The number:
[CODE]19910687762134192670118862096067392465664968300342548919354552757803836366452553513723707267540151136757054294612102971844499435204205184562837462781951869899[/CODE]

A nice poly is requested.

I haven't done a poly search for the thread in a while. I'll start at coeff 17M.
-Curtis

I'll run it overnight with lower coefficients and see what shows up.

Best so far:

[CODE]
expecting poly E from 1.83e-012 to > 2.11e-012

# norm 2.827747e-015 alpha -7.037194 e 1.871e-012 rroots 3
skew: 7467977.93
c0: -227324950438094504341897974825045123616
c1: 441431187345941284551928356099268
c2: 61992273776179855339421580
c3: -16591339896350187095
c4: -1755544758814
c5: 105672
Y0: -2851184609472234474936745662905
Y1: 140548861923230521[/CODE]

I'll let it keep running through the day and see if anything better shows itself.

My best after 18hr is 1.67. I'll give it until Saturday afternoon.

Slightly better than my previous:

[CODE]# norm 2.989314e-015 alpha -6.068499 e 1.950e-012 rroots 5
skew: 3401918.85
c0: -13297443448158163452460603694102719568
c1: 22635803858286922688706261302478
c2: 16765449785786855484708203
c3: -6992317638830850837
c4: -1581411502719
c5: 138060
Y0: -2702736620183834169400905694227
Y1: 129049292409660137[/CODE]

36hr total, ~400 stage 2 hits better than 6e+20. Best was 1.67.

I am on a short trip for next 2 days, so I will try no further for this candidate.

Wombatman- Can you give me a rough idea of how many hits at what bound you found? I'd like to get a feel for how slow my laptop GPU/CPU combo is for this work.

Curtis,

I divided the default stage 2 norm by 10 and set my min e-value to 1.7e-12. My minimum coefficient was 100,000. In the course of ~24 hours, I covered 100,000 to ~140,000 using 8 threads on my GPU, but I also was lazy and just used "-np" rather than "-np1 -nps" followed by "-npr" to maximize throughput.

Hope that helps.

[QUOTE=frmky;352501]How about 3,697+?[/QUOTE]
Poly selection for 3,697+ is starting. Contributions are welcome!

Just to make sure I have the right number--this C221?

[CODE]13146147859355563057184294559227261909344194891313875731887908004819237997799717180543008861151256660634764426562411254982358980217588777809948725583888752636571464476553521798328361714719161395717184464823416688122796421
[/CODE]

Likely yes. It's the right length and starts and ends with the right numbers. :-)