XYYXF Status Update

[swellman]

Here are the XYYXF composites as of April 2022.

One XYYXF is currently in GNFS by NFS@Home (C203_145_119) and has been omitted from the list.

[ryanp]

Originally Posted by swellman

Here are the XYYXF composites as of April 2022.

One XYYXF is currently in GNFS by NFS@Home (C203_145_119) and has been omitted from the list.

2 hits so far:

http://factordb.com/index.php?id=1000000000044714162
http://factordb.com/index.php?id=1000000000044736161

[swellman]

XYYXF composites fully factored by Ryan Propper with ECM to date, shown as y_x_factor

95 138 137569872848618079168497788857665619070975508959085977
138 148 7148255126578794765422102122909172289268236979484218129
129 134 135670046698656711152317371191955389273883979954729787
111 139 2063202949990066743163751168921243267735542983816410497
81 146 103789758477794842211009755052743245746201848433761791953858611
124 141 133772128399353454302680369792367376604503532782027043821
148 149 164765011194494108378059619015812662809204025271338322937
118 148 3467745961171660748432832903372059871377664084616835703029
117 137 355804711213846224168595689144120149507294880133429929563
*136 150 633173149104321439701718688310849360699588006217613940817
122 145 95036826689253348122504549139573274683669492870863332268717
137 146 3118411803907757802223601737311246433663432677717416325331
129 140 43916092452583705950200190784289292829644462213724298857250903
123 134 8899027269008140316373707126027525152867402686853175806476907

*136^150+150^136 had a c145 stub remaining after ECM but Ryan quickly factored it. His efforts here are much appreciated.

Note that 149^148+148^149 was a SNFS difficulty of 323. Thank goodness for ECM!

[VBCurtis]

Originally Posted by swellman

But the next batch on my list are 4 composites of SNFS 270. Can you run 1000 @65e7 and 800 @12e8 on these? Your efforts would greatly speed thing up.

C217_146_130
2273736614959600102299788369214860151882556046845135920321491916509566649822233346525551566590304365550486243473007049647802844778464741732324121635941624450635826410351378351500756252260898809587472865957974314446269

First one done (quoted number for clarity), 1000@65e7 and 800@12e8.
Starting second one now.
Haven't finished building the new desktop yet, which is why this is taking 3x as long as I expected.

[swellman]

Thank you!

[swellman]

Yoyo factored C222_141_82 with ECM @B1=260e6 when a p62 fell out. There is much fertile ground remaining for ECM in the XYYXF project at the higher levels (t60 and above).

[VBCurtis]

Originally Posted by swellman

Can you run 1000 @65e7 and 800 @12e8 on these? Your efforts would greatly speed thing up.

C214_139_87
4195620243915888279671778712345331475268709716797825786349176460911223003450368828626222652158705793360957647290504936745524043932410659915735237866241362258201645994955743683282475290187203096154867195374771993153

Second ECM run complete, on the number quoted here.
The third of four in the list was factored by yoyo; I'll work on #4 in a week or so when I finish ECM on 13_2_929m1.

[swellman]

Much appreciated!

[swellman]

Ryan found a p70 in C251_131_128 using ECM with B1=850M. A remarkable find and 131^128+128^131 is fully factored to boot.

GMP-ECM 7.0.5-dev [configured with GMP 6.2.0, GWNUM 30.4, --enable-asm-redc, --enable-assert] [ECM]
Due to incompatible licenses, this binary file must not be distributed.
Input number is (128^131+131^128)/11993361557350502659918593 (251 digits)
Using B1=850000000, B2=15892628251516, polynomial Dickson(30), sigma=1:2738913657
Step 1 took 2574357ms
Step 2 took 597709ms
********** Factor found in step 2: 
2396647352628340730333265310821035979852802473169960235597808820903739
Found prime factor of 70 digits: 
2396647352628340730333265310821035979852802473169960235597808820903739
Prime cofactor ((128^131+131^128)/11993361557350502659918593)/2396647352628340730333265310821035979852802473169960235597808820903739 has 182 digits