Contributing to Cunningham Project - Page 18

sweety439 · 2020-10-22, 06:36

Why 10^371+-1 are factored earlier than 10^365+-1? eulerphi(371) = 312 > 288 = eulerphi(365)

VBCurtis · 2020-10-22, 08:56

Quote:

Originally Posted by sweety439

Why 10^371+-1 are factored earlier than 10^365+-1? eulerphi(371) = 312 > 288 = eulerphi(365)

What relevance does this information have to do with deciding which to factor first?

charybdis · 2021-01-11, 19:17

Sam Wagstaff just knocked 2,2390M down to c191 with ECM.
No-one has reserved it yet - could this be a target for a short forum team sieve?

VBCurtis · 2021-01-11, 19:33

Sure! I can start poly select this evening. Can you contact Sam to reserve it for MersenneForum?

charybdis · 2021-01-11, 19:42

Quote:

Originally Posted by VBCurtis

Sure! I can start poly select this evening. Can you contact Sam to reserve it for MersenneForum?

Done. I suppose it's possible he's already started working on it himself and just hasn't got round to updating the reservation page, so I'll keep everyone updated.

What parameters are you using for polyselect, so I know not to overlap with you?

VBCurtis · 2021-01-11, 19:58

I figured I'd start after you, so I'd work around whatever region you select.
I'm fine with using admin of your admax, and incr of 2310 or 4620 to cover a large region up there.

charybdis · 2021-01-11, 20:19

Got the go-ahead from Sam.

I'll do P=5M, admax=10M, incr=420.

VBCurtis · 2021-01-11, 23:49

Taking admin 15M, admax 60M, incr 4620, P=4M.

That leaves 10-15M / incr 420 for anyone else to contribute on CADO if they choose.

firejuggler · 2021-01-12, 03:14

I've got a 1.377e-14 with Msieve, trying to use cado to spin it up.
Record is around 2e-14 so still a bit far

charybdis · 2021-01-12, 17:20

The best from my run, by some margin, is

Code:

n: 28653448550423582065969107478752150888235561427247664110066527668159681894430155521476413904809897034030256344677647748498114768327844226758360594247371333432148627535343266861185808662829021
skew: 61160593.83
c0: -782066809369899992846921498396677009099575965
c1: 129978232145697650128010452670728125268
c2: 1136403038232649046041648047998
c3: -50366553898678575377716
c4: 291334628577375
c5: 2637600
Y0: -6410674956398678515938860432260175622
Y1: 195016503229310813759987119

Cownoise scores this as 2.023e-14. I tried spinning with EdH's script but didn't get an improvement.

firejuggler · 2021-01-12, 17:48

That's still close to the record for a C191, so good enough?
afaik

Code:

...

 191    2.108e-14    EdH/spin              06-20    kosta M61^16+1
...

from the best poly score

2021-01-11, 23:49	#195
VBCurtis "Curtis" Feb 2005 Riverside, CA 1243₁₆ Posts	Taking admin 15M, admax 60M, incr 4620, P=4M. That leaves 10-15M / incr 420 for anyone else to contribute on CADO if they choose. Last fiddled with by VBCurtis on 2021-01-11 at 23:50

2021-01-12, 17:48	#198
firejuggler Apr 2010 Over the rainbow 100111100001₂ Posts	That's still close to the record for a C191, so good enough? afaik Code: ... 191 2.108e-14 EdH/spin 06-20 kosta M61^16+1 ... from the best poly score Last fiddled with by firejuggler on 2021-01-12 at 18:05

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2020-10-22, 06:36	#188
sweety439 Nov 2016 2²×3×5×47 Posts	Why 10^371+-1 are factored earlier than 10^365+-1? eulerphi(371) = 312 > 288 = eulerphi(365)

2021-01-11, 19:17	#190
charybdis Apr 2020 193₁₀ Posts	Sam Wagstaff just knocked 2,2390M down to c191 with ECM. No-one has reserved it yet - could this be a target for a short forum team sieve?

2021-01-11, 19:33	#191
VBCurtis "Curtis" Feb 2005 Riverside, CA 5²·11·17 Posts	Sure! I can start poly select this evening. Can you contact Sam to reserve it for MersenneForum?

2021-01-11, 19:58	#193
VBCurtis "Curtis" Feb 2005 Riverside, CA 5²·11·17 Posts	I figured I'd start after you, so I'd work around whatever region you select. I'm fine with using admin of your admax, and incr of 2310 or 4620 to cover a large region up there.

2021-01-11, 20:19	#194
charybdis Apr 2020 193 Posts	Got the go-ahead from Sam. I'll do P=5M, admax=10M, incr=420.

2021-01-12, 03:14	#196
firejuggler Apr 2010 Over the rainbow 9E1₁₆ Posts	I've got a 1.377e-14 with Msieve, trying to use cado to spin it up. Record is around 2e-14 so still a bit far