Fails to find very small factors.

Mr. P-1 · 2013-03-21, 06:33

My understanding (which matches my experience) was that factorDB will trial factor any new composite it is given, to a low level. Just now, intending to enter the following number -1, I forgot to subtract the 1

Code:

2*3*5*29*11*7*13*37*17*79*23*4129*193*2593*101*19*39163*577*26431*131*308798542881428667318174028327605372989*103*163*179*293*127*6287*683437*31*89*13590243019242466336587034391*113*2207*59*109*223*2351*62861*4651*43*53*669301*1087*7477*817246446020375245871694881*41*323717*187273*83*337*1327*431*739*15137*5659*47*4086059*97*93557*827923*569*281*2129*1033*433*82373*239*263*1217*719*4931*383*769*60149*4049*620663

I was very surprised that it failed to find most of the factors, including 3 and 5. I told it about 3. At the time of posting, it still doesn't know about 5.

axn · 2013-03-21, 07:41

http://factordb.com/status.php doesn't list any cores dedicated to small TF (it used to have). My guess is that this feature was removed a long while ago.

/me vaguely remembers similar problems a while back

Mr. P-1 · 2013-03-21, 08:35

It doesn't need to do any TF. The factors are in the query string.

axn · 2013-03-21, 12:13

Quote:

Originally Posted by Mr. P-1

It doesn't need to do any TF. The factors are in the query string.

I guess it is not too intelligent. Sees an expression. Computes the expression. Sticks it in the db.

Mini-Geek · 2013-03-21, 13:13

Quote:

Originally Posted by axn

I guess it is not too intelligent. Sees an expression. Computes the expression. Sticks it in the db.

I seem to recall it being more intelligent than that, recognizing the factors when you enter a number as a product of values. Perhaps this is related to the TF worker being disabled?

Batalov · 2013-03-21, 17:42

Quote:

Originally Posted by Mr. P-1

Fails to find very small factors.

One cannot fail if one doesn't try.

“Do. Or do not! There is no try.” --Yoda

ATH · 2013-03-22, 02:30

Quote:

Originally Posted by Batalov

“Do. Or do not! There is no try.” --Yoda

"You tried your best, and you failed miserably. The lesson is, never try." -- Homer Simpson

2013-03-21, 06:33	#1
Mr. P-1 Jun 2003 7·167 Posts	Fails to find very small factors. My understanding (which matches my experience) was that factorDB will trial factor any new composite it is given, to a low level. Just now, intending to enter the following number -1, I forgot to subtract the 1 Code: 2352911713371779234129193259310119391635772643113130879854288142866731817402832760537298910316317929312762876834373189135902430192424663365870343911132207591092232351628614651435366930110877477817246446020375245871694881413237171872738333713274317391513756594740860599793557827923569281212910334338237323926312177194931383769601494049620663 I was very surprised that it failed to find most of the factors, including 3 and 5. I told it about 3. At the time of posting, it still doesn't know about 5. Last fiddled with by Mr. P-1 on 2013-03-21 at 06:33*

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2013-03-21, 07:41	#2
axn Jun 2003 3·5·17·19 Posts	http://factordb.com/status.php doesn't list any cores dedicated to small TF (it used to have). My guess is that this feature was removed a long while ago. /me vaguely remembers similar problems a while back

2013-03-21, 08:35	#3
Mr. P-1 Jun 2003 7·167 Posts	It doesn't need to do any TF. The factors are in the query string.