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Old 2010-09-05, 21:27   #287
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Quote:
Originally Posted by Charles
I have now proved the primality of 618970019642690137449562111, a p27, with trial division. This was the hardest proof by trial division I had ever attempted.
Please, tell me, exactly how did your computer's speed increase exponentially?

If it took me about 10-15 minutes to prove a p22 prime; It should have taken you a similar timeframe to prove the same number prime; A number ≈70000-75000 times that size should have taken many thousands of times longer.

Or did you get started 3-6 months ago?

Last fiddled with by 3.14159 on 2010-09-05 at 21:30
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Old 2010-09-05, 21:29   #288
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Originally Posted by 3.14159 View Post
Please, tell me, exactly how did your computer's speed increase exponentially?
You should look closer here. That's what I meant!

618970019642690137449562111 = 2^89-1 and therfore only factors = 2kp+1 have to be considered and tested!

Last fiddled with by kar_bon on 2010-09-05 at 21:30
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Old 2010-09-05, 21:32   #289
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Quote:
Originally Posted by Karsten
618970019642690137449562111 = 2^89-1 and therfore only factors = 2kp+1 have to be considered and tested!
Mersenne number? Cheating not allowed,

General numbers only. Optionally, Proth numbers. Take a probable prime and prove it prime, using trial-factoring only.

So, Charles, try again, with a general or Proth number. (Can either be b = 2 or regular). Unless your computer speeds up by 10000 on demand, let's see how that works out.

Last fiddled with by 3.14159 on 2010-09-05 at 21:36
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Old 2010-09-05, 21:34   #290
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Originally Posted by 3.14159 View Post
Mersenne number? Cheating not allowed
Really... did you think I'd enter into one of these without some sort of trick?
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Old 2010-09-05, 21:48   #291
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Quote:
Originally Posted by Charles
Really... did you think I'd enter into one of these without some sort of trick?
The first was composite, divisible by 7, and the next is a Mersenne number.

You so far have contributed nothing. Next!
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Old 2010-09-05, 21:52   #292
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Reporting for 17 or 18: (981248619155265231198804096876768467232996282812538785080944608471724730019235498676*3000!+1)/486830979235504387397288386896757349991446828735164830762828213017832532827952201 is prime, 9051 digits.

This may probably be in Special Cofactor.

Last fiddled with by 3.14159 on 2010-09-05 at 21:53
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Old 2010-09-05, 21:55   #293
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Quote:
Originally Posted by 3.14159 View Post
The first was composite, divisible by 7, and the next is a Mersenne number.

You so far have contributed nothing. Next!
the one thing i see you contributing to most is a headache by changing rules so much.
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Old 2010-09-05, 22:27   #294
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Originally Posted by science_man_88
the one thing i see you contributing to most is a headache by changing rules so much.
I'm merely keeping trickeries out of the list.

Last fiddled with by 3.14159 on 2010-09-05 at 22:27
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Old 2010-09-05, 22:29   #295
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Quote:
Originally Posted by 3.14159 View Post
The first was composite, divisible by 7
Copy/paste error. I fixed it before you posted, but you quoted the unedited version.

Last fiddled with by CRGreathouse on 2010-09-05 at 22:31
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Old 2010-09-05, 22:30   #296
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Quote:
Originally Posted by science_man_88 View Post
the one thing i see you contributing to most is a headache by changing rules so much.
+1. If I had a nickel for every time he did that... well, I'd have about a buck. But still, that's a lot of rules changes.
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Old 2010-09-05, 22:43   #297
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Originally Posted by CRGreathouse View Post
+1. If I had a nickel for every time he did that... well, I'd have about a buck. But still, that's a lot of rules changes.
And it's a ridiculous point of his list:

1. Wasting CPU-cycles to find the biggest prime proven by trial division.
2. He can't recognize simple 'easy' numbers.
3. He can't prove if such number is proven only by trial division.

Last fiddled with by kar_bon on 2010-09-05 at 23:07
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