mersenne.ca - Page 92

James Heinrich · 2023-01-27, 02:13

Quote:

Originally Posted by LordJulius

when the 'known factors' or 'either' box checked, the results TF column will show TFs below 2^67.

Thanks, fixed.

harlee · 2023-01-28, 16:51

I was looking at the default results returned by Factoring Beyond First Factor and Exponents that were poorly P-1 factored and I have a couple of questons. For the same exponent the two pages returns different Pminus1 bounds:

Factoring Beyond First Factor (Optional Fixed B1 field is blank)

Pminus1=1,2,4180471,-1,100000,100000,67,"44685391937063190031,1112388632373104350711"

Exponents that were poorly P-1 factored

Pminus1=1,2,4180471,-1,220000,6600000,67,"1112388632373104350711,44685391937063190031"

Previously tested with B1=45000 B2=630000

Why is the default B1 and B2 bounds different? As of the B2 bound, I know that for v30.8b? if B2 is either equal to 0 or B2 is equal to B1 then Prime95 will calculate the B2 bounds. Just did a quick test on the latter Pminus1 line (B1=220000, B2=6600000) and v30.8b15 ignored the B2 bound and calculated its own B2 bound. Anyway, is B2=6600000 originally set for v30.7 and earlier Prime95 software?

James Heinrich · 2023-01-28, 19:42

Quote:

Originally Posted by harlee

Maybe add an option to return B2 bounds for ether v30.7 and earlier versions or v30.8 and later versions.

At best I have a poor-man's version of the bounds calculations from v30.7, I do not have any means to calculate v30.8+ bounds.

morefactors: uses "generous" bounds: B1 is calculated using the standard bounds calculation, using the "max" variant of B1, then doubled.

pm1_worst: uses "massive" bounds: Pfactor "tests saved" is set as high as 10 (<5M) down to no less than 2 (>40M). Pminus1 bounds again use the B1_max value, but multiplied by the number of tests saved. If existing B1 of existing P-1 test large, it will ensure that the new B1 is at least 20% bigger than previous B1.

Clearly these bounds calculations are not suitable for first-time wavefront P-1 work, they're designed as a starting point for doing 2nd/3rd/Nth P-1 test on previously-tested exponents (which sometimes have already had 10 or more P-1 tests of varying quality).

harlee · 2023-01-28, 21:19

Thank you for the explanation about the differences.

2023-01-28, 16:51	#1003
harlee Sep 2006 Odenton, MD, USA BE₁₆ Posts	I was looking at the default results returned by Factoring Beyond First Factor and Exponents that were poorly P-1 factored and I have a couple of questons. For the same exponent the two pages returns different Pminus1 bounds: Factoring Beyond First Factor (Optional Fixed B1 field is blank) Pminus1=1,2,4180471,-1,100000,100000,67,"44685391937063190031,1112388632373104350711" Exponents that were poorly P-1 factored Pminus1=1,2,4180471,-1,220000,6600000,67,"1112388632373104350711,44685391937063190031" Previously tested with B1=45000 B2=630000 Why is the default B1 and B2 bounds different? As of the B2 bound, I know that for v30.8b? if B2 is either equal to 0 or B2 is equal to B1 then Prime95 will calculate the B2 bounds. Just did a quick test on the latter Pminus1 line (B1=220000, B2=6600000) and v30.8b15 ignored the B2 bound and calculated its own B2 bound. Anyway, is B2=6600000 originally set for v30.7 and earlier Prime95 software? Last fiddled with by harlee on 2023-01-28 at 17:04 Reason: Delete on line, added exponenet link and previous bounds

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2023-01-28, 21:19	#1005
harlee Sep 2006 Odenton, MD, USA 2×5×19 Posts	Thank you for the explanation about the differences.