alright Fermat divisors, ya can run....

ixfd64 · 2004-05-24, 22:17

...but ya can't hide.

Seriously, though... Anyone notice the huge gap between the discovery of Fermat divisors? I mean, it's been almost 7 months since the last Fermat divisor was discovered. Is the project even running?

Well, on the bright side, a longer gap can sometimes mean a bigger surprise! :)

---
*makes funny face at next poster*

ET_ · 2004-05-25, 12:40

Quote:

Originally Posted by ixfd64

...but ya can't hide.

Seriously, though... Anyone notice the huge gap between the discovery of Fermat divisors? I mean, it's been almost 7 months since the last Fermat divisor was discovered. Is the project even running?

The Project is up and running.

I received many updates from Fermat's factors searchers :-)

Luigi

philmoore · 2004-05-25, 17:14

Quite a few large Proth primes have been discovered in the past six months, but as luck would have it, none of them proved to be a Fermat number divisor. But sooner or later...

jinydu · 2004-05-26, 01:50

What is the smallest Fermat number whose primality status is unknown?

ixfd64 · 2004-05-26, 02:53

I believe it's F33.

akruppa · 2004-05-26, 05:51

It is, according to Wilfrid Keller's status page.

ewmayer · 2004-05-26, 14:29

Quote:

Originally Posted by akruppa

It is, according to Wilfrid Keller's status page.

And if anyone would know, it would be Alex. ;)

jinydu · 2004-05-27, 00:26

"Composite but no factor known m = 14, 20, 22, 24"

So there is a primality test for Fermat numbers that doesn't require finding a factor?

ixfd64 · 2004-05-27, 05:01

Well, there's Pepin's test, but the numbers quickly grow too large for it.

jinydu · 2004-05-27, 05:42

Hmm. F25 already has over 10.1M digits.

No wonder... Mersenne Numbers grow exponentially while Fermat Numbers grow "double exponentially".

2004-05-24, 22:17	#1
ixfd64 Bemusing Prompter "Danny" Dec 2002 California 2·5·239 Posts	alright Fermat divisors, ya can run.... ...but ya can't hide. Seriously, though... Anyone notice the huge gap between the discovery of Fermat divisors? I mean, it's been almost 7 months since the last Fermat divisor was discovered. Is the project even running? Well, on the bright side, a longer gap can sometimes mean a bigger surprise! :) --- makes funny face at next poster

2004-05-27, 05:42	#10
jinydu Dec 2003 Hopefully Near M48 2×3×293 Posts	Hmm. F25 already has over 10.1M digits. No wonder... Mersenne Numbers grow exponentially while Fermat Numbers grow "double exponentially". Last fiddled with by jinydu on 2004-05-27 at 05:43

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2004-05-25, 17:14	#3
philmoore "Phil" Sep 2002 Tracktown, U.S.A. 3·373 Posts	Quite a few large Proth primes have been discovered in the past six months, but as luck would have it, none of them proved to be a Fermat number divisor. But sooner or later...

2004-05-26, 01:50	#4
jinydu Dec 2003 Hopefully Near M48 2·3·293 Posts	What is the smallest Fermat number whose primality status is unknown?

2004-05-26, 02:53	#5
ixfd64 Bemusing Prompter "Danny" Dec 2002 California 4526₈ Posts	I believe it's F33.

2004-05-26, 05:51	#6
akruppa "Nancy" Aug 2002 Alexandria 2,467 Posts	It is, according to Wilfrid Keller's status page.

2004-05-27, 00:26	#8
jinydu Dec 2003 Hopefully Near M48 2·3·293 Posts	"Composite but no factor known m = 14, 20, 22, 24" So there is a primality test for Fermat numbers that doesn't require finding a factor?

2004-05-27, 05:01	#9
ixfd64 Bemusing Prompter "Danny" Dec 2002 California 2×5×239 Posts	Well, there's Pepin's test, but the numbers quickly grow too large for it.