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 2010-07-11, 13:29 #1 science_man_88     "Forget I exist" Jul 2009 Dartmouth NS 2×52×132 Posts lucas lehmer outstretch I was told to post on the forum instead of annoying CRGreathouse. so here I am basically i wan't to find a way to easily connect certain p values with s in a new way. s2-2 =k*2p-1 (s2-2)/k + 1 = 2p p=log2((s2-2)/k + 1) this works for s(n-1) can we figure out a generalisation for any amount of n change ? if so can we apply it easily and can anyone get the log2() part reduced more ?
2010-07-11, 13:34   #2
retina
Undefined

"The unspeakable one"
Jun 2006
My evil lair

2×3×1,129 Posts

Quote:
 Originally Posted by science_man_88 s2-2 =k*2p-1 (s2-2)/k + 1 = 2p
Where did you learn your algebra? I'd ask for my money back if I was you.

2010-07-11, 14:03   #3
CRGreathouse

Aug 2006

22·3·499 Posts

There's an arithmetic error in your post.

Quote:
 Originally Posted by science_man_88 this works for s(n-1) can we figure out a generalisation for any amount of n change ? if so can we apply it easily and can anyone get the log2() part reduced more ?
I don't understand your goal here. What does "for any amount of n change" mean? What does "get the log2() part reduced more" mean?

2010-07-11, 16:08   #4
science_man_88

"Forget I exist"
Jul 2009
Dartmouth NS

2×52×132 Posts

Quote:
 Originally Posted by CRGreathouse There's an arithmetic error in your post. I don't understand your goal here. What does "for any amount of n change" mean? What does "get the log2() part reduced more" mean?
I can't find the error you talk of, and if it's truly incorrect then why care for either answer.

sorry log2(2^p)

Last fiddled with by science_man_88 on 2010-07-11 at 16:09

 2010-07-11, 16:14 #5 science_man_88     "Forget I exist" Jul 2009 Dartmouth NS 2·52·132 Posts s2-2 =k*(2p-1) =correction (s2-2)/k =2p-1 ((s2-2)/k)+1 =2p log2(((s2-2)/k)+1) =p Last fiddled with by science_man_88 on 2010-07-11 at 16:15
2010-07-11, 16:20   #6
science_man_88

"Forget I exist"
Jul 2009
Dartmouth NS

2×52×132 Posts

Quote:
 Originally Posted by CRGreathouse There's an arithmetic error in your post. I don't understand your goal here. What does "for any amount of n change" mean? What does "get the log2() part reduced more" mean?
the n change part means for any s within the sequence (so for 2^5-1 instead of using the 5th one in the sequence; n=4 as n=0 for the first; I could try and use a lower number.) the reason a wanted the log2(((s2-2)/k)+1) reduced is to get a lower comparison of s and p. like p*k isn't that big compared with k*2^p-1 same idea in reducing the log.

2010-07-13, 00:16   #7
science_man_88

"Forget I exist"
Jul 2009
Dartmouth NS

845010 Posts

Quote:
 Originally Posted by science_man_88 the n change part means for any s within the sequence (so for 2^5-1 instead of using the 5th one in the sequence; n=4 as n=0 for the first; I could try and use a lower number.) the reason a wanted the log2(((s2-2)/k)+1) reduced is to get a lower comparison of s and p. like p*k isn't that big compared with k*2^p-1 same idea in reducing the log.
s=4;*

 2010-07-14, 12:35 #8 science_man_88     "Forget I exist" Jul 2009 Dartmouth NS 2·52·132 Posts log2(((s^4 - 4*s^2 + 2)/k)+1) = p is the next one up. I can continue this but the equations get longer and without getting a lower fraction to go with it works out to log(Mersenne number(p) +1) which isn't very helpful.

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