question about residues

davar55 · 2016-04-16, 18:48

How would I check whether the value my LL program
gets for a hex residue matches P95's value?

I know 2^371561-1 is tiny, but I'm range checking
my program and it reported this composite, of course,
and I'd just like to corroborate identical residues.

ATH · 2016-04-16, 19:30

Take your final residue and do a mod 2⁶⁴ and then convert it to hexadecimal.

If you start with S₀=4 then:

Res64 = S_p-2 (mod 2⁶⁴)

davar55 · 2016-04-16, 19:35

Yes that's how it's reported. Where can I find
the residue reported for this exponent by P95?
(I mean the mod 64 hex residue.)

TheJudger · 2016-04-16, 20:44

http://www.mersenne.org/report_exponent/?exp_lo=371561

davar55 · 2016-04-17, 08:31

Thanks. That was exactly what I needed.

My version of LL confirms the same non-zero residue.

2016-04-16, 18:48	#1
davar55 May 2004 New York City 10212₈ Posts	question about residues How would I check whether the value my LL program gets for a hex residue matches P95's value? I know 2^371561-1 is tiny, but I'm range checking my program and it reported this composite, of course, and I'd just like to corroborate identical residues.

2016-04-16, 19:30	#2
ATH Einyen Dec 2003 Denmark 3⁵×13 Posts	Take your final residue and do a mod 2⁶⁴ and then convert it to hexadecimal. If you start with S₀=4 then: Res64 = S_p-2 (mod 2⁶⁴) Last fiddled with by ATH on 2016-04-16 at 19:31

2016-04-16, 19:35	#3
davar55 May 2004 New York City 2·29·73 Posts	Yes that's how it's reported. Where can I find the residue reported for this exponent by P95? (I mean the mod 64 hex residue.) Last fiddled with by davar55 on 2016-04-16 at 19:37

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2016-04-16, 20:44	#4
TheJudger "Oliver" Mar 2005 Germany 11×101 Posts	http://www.mersenne.org/report_exponent/?exp_lo=371561

2016-04-17, 08:31	#5
davar55 May 2004 New York City 4234₁₀ Posts	Thanks. That was exactly what I needed. My version of LL confirms the same non-zero residue.