C197_148_45
 

C197_148_45

[code]
n: 15329895267044302873891174984944617312806978355057983047383161451244893344826822099919196732930271476610619814172093285276608197494910298520152145552947810495264359766139916240459649381787095666477
# 148^45+45^148, difficulty: 249.38, anorm: 3.38e+040, rnorm: 1.19e+046
# scaled difficulty: 249.38, suggest sieving rational side
# size = 9.088e-013, alpha = 0.000, combined = 1.168e-013, rroots = 0
type: snfs
size: 249
skew: 4.58
c5: 1
c0: 2025
Y1: 34068690316840665088
Y0: -39479842665806602234295041487552225589752197265625
[/code]

[QUOTE=swellman;451955]C197_148_45

[code]
n: 15329895267044302873891174984944617312806978355057983047383161451244893344826822099919196732930271476610619814172093285276608197494910298520152145552947810495264359766139916240459649381787095666477
# 148^45+45^148, difficulty: 249.38, anorm: 3.38e+040, rnorm: 1.19e+046
# scaled difficulty: 249.38, suggest sieving rational side
# size = 9.088e-013, alpha = 0.000, combined = 1.168e-013, rroots = 0
type: snfs
size: 249
skew: 4.58
c5: 1
c0: 2025
Y1: 34068690316840665088
Y0: -39479842665806602234295041487552225589752197265625
[/code][/QUOTE]

I did some test sieving with this polynomial and with the (IMO) somewhat more obvious polynomial given by
[code]
c5: 1
c0: 375
Y1: 2631989511053773482286336099170148372650146484375
Y0: -34068690316840665088
[/code]

The latter turned out to sieve substantially better. In fact so much so that I think it actually works out better as a 31-bit job. Not a great yield, but it should do the job.

[QUOTE=jyb;452034]I did some test sieving with this polynomial and with the (IMO) somewhat more obvious polynomial given by
[code]
c5: 1
c0: 375
Y1: 2631989511053773482286336099170148372650146484375
Y0: -34068690316840665088
[/code]

The latter turned out to sieve substantially better. In fact so much so that I think it actually works out better as a 31-bit job. Not a great yield, but it should do the job.[/QUOTE]
Hmm... Yafu goof?

[QUOTE=Dubslow;452037]Hmm... Yafu goof?[/QUOTE]

Either Yafu or the goof using it!

[QUOTE=jyb;452034]I did some test sieving with this polynomial and with the (IMO) somewhat more obvious polynomial given by
[code]
c5: 1
c0: 375
Y1: 2631989511053773482286336099170148372650146484375
Y0: -34068690316840665088
[/code]

The latter turned out to sieve substantially better. In fact so much so that I think it actually works out better as a 31-bit job. Not a great yield, but it should do the job.[/QUOTE]

Glad you found a better poly for a proper 14e/31 job. Thanks for queuing it.

C160 from aliquot sequence 11040:

[CODE]n: 4409532288489507333192213562147876845858469211971052677426795037544285442856497325035968905612741429947472557253258960082522920912787534519079753213510746880477
skew: 9585821.81
c0: -1395226932920371783655399374640500722728
c1: 787057682706312479937484965784314
c2: 162253448848063731693547989
c3: -81843495325963337576
c4: -2399371743138
c5: 48060
Y0: -9829283146069545412959458697837
Y1: 212129417225543797
rlim: 60000000
alim: 60000000
lpbr: 30
lpba: 30
mfbr: 60
mfba: 60
rlambda: 2.6
alambda: 2.6
lss: 0[/CODE]

OPN from the Most Wanted Road Block [URL=http://www.lirmm.fr/~ochem/opn/mwrb2000.txt]file[/URL] is ready.

4018159^37-1 (C238) SNFS-245

C256 from XYYXF that has been ECM'd. Seems like a fit for 15e:

[CODE]n: 2279019635262178260223610372866161113233537351181247262995589386985378698045180235228538838348697209388279801210996958280092611824762735859504092308376304672536049578066139601245777058442691694530960357274040042752387753146406894539941430545737889457466479
# 127^121+121^127, difficulty: 266.60, anorm: 2.48e+38, rnorm: 5.33e+49
# scaled difficulty: 268.49, suggest sieving rational side
# size = 2.087e-13, alpha = 1.491, combined = 3.768e-14, rroots = 0
type: snfs
size: 266
skew: 1.0081
c6: 121
c0: 127
Y1: -1191446152405248657777607437681912764659201
Y0: 54763699237492901685126120802225273763666521
m: 1662494550986228882566228817664053580038096714821209997934679199277061987019250219666195095292608720990844899512073487570488175183098414434723678817318610879312388031432395464414980456036350664791631044752565052965047488994184947124894919850559221309624285
rlim: 79600000
alim: 79600000
lpbr: 32
lpba: 32
mfbr: 64
mfba: 64
rlambda: 2.6
alambda: 2.6[/CODE]

Parameters chosen by YAFU and polynomial chosen as the best by trial sieving.

Shouldn't rlim/alim be higher than 80e6 for a 15e/32 job?

Seems like a/rlim=200M, a/rlambda=2.8 would be a bit better though it's ultimately the gatekeeper's call.

[QUOTE=VBCurtis;452355]Shouldn't rlim/alim be higher than 80e6 for a 15e/32 job?[/QUOTE]

[QUOTE=swellman;452361]Seems like a/rlim=200M, a/rlambda=2.8 would be a bit better though it's ultimately the gatekeeper's call.[/QUOTE]

I readily admit I have no idea what it should be and am going with YAFU's choices. If anybody can suggest some good rules of thumb, I'm all ears.:smile: