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Old 2006-01-14, 17:13   #12
Kosmaj
 
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Quote:
I haven't written that program between 14 Jan 06 03:39 PM and 03:51 PM.
Yes, I guess you began after writing message #259? As for limits I'm using kmin=15 and kmax between 1E15 and 1E16 (for the time being).
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Old 2006-01-14, 17:30   #13
Kosmaj
 
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Default n=57

Found first DodecaProth for n=57:
87653084113035 57

And imagine, for such a small k<100T.
Has one extra leg to the left, none to the right.
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Old 2006-01-14, 18:15   #14
R. Gerbicz
 
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Default No more dodecaproth for n=52

I've searched the full range for n=52 to find all dodecaproth.
Here is the full report: on Pentium4 Celeron 1.7 GHz:
C:\>dodeca_1_0 52 1 4503599627370495
You can also find the k n values in results_dodeca.txt file ( These are 3-probable primes )
n=52, kmin=1, kmax=4503599627370495, version=1.0
Starting the sieve...
Using the first 10 primes to reduce the size of the sieve array
2808528662035845 52
The sieving is complete.
Number of Prp tests=613089
Time=8917 sec.

Ps. I've verified all 12 numbers are primes.

Last fiddled with by R. Gerbicz on 2006-01-14 at 18:17
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Old 2006-01-14, 18:15   #15
tcadigan
 
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I don't get all the other stuff with legs and everything. just ran the program (dodeca_1_0.exe) here's what I got:

n=66, kmin=1, kmax=1000000000000000, version=1.0
Starting the sieve...
Using the first 10 primes to reduce the size of the sieve array
229350894172785 66
The sieving is complete.
Number of Prp tests=138495
Time=2992 sec.
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Old 2006-01-14, 18:36   #16
R. Gerbicz
 
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Probably we can start a new thread for reservation for dodecaproth search, to avoid the duplication.

Quote:
Originally Posted by Kosmaj
Yes, I guess you began after writing message #259?
Yes.

Last fiddled with by R. Gerbicz on 2006-01-14 at 18:39
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Old 2006-01-15, 00:58   #17
Kosmaj
 
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Congrats to tcadigan for a new DodecaProth! I found 3 for n=62:

99828673281855 62
286846836764775 62
1692654062704395 62


BTW, I checked n=56 to 1200T (1.2E15) and n=57-62 to 2000T (2E15) but besides the one for n=57 I found none. I'm proceeding with n=63-70 to 2000T (will skip n=66).
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Old 2006-01-15, 10:23   #18
Kosmaj
 
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Default R. Gerbicz

I noticed a large slow-down of dodeca.exe ver. 1.0 on a large range. Have a look. Case 1:
Code:
 
n=70, kmin=15, kmax=3000000000000000, version=1.0
Using the first 10 primes to reduce the size of the sieve array
Time=1968 sec.
Case 2:
Code:
n=70, kmin=3000000000000000, kmax=10000000000000000, version=1.0
Using the first 11 primes to reduce the size of the sieve array
   Status: 0.3 percentage of the project is complete. Time thusfar: 69 sec.
I stopped the second instance but 0.3% in 69 sec means 23000 sec for the range 7000T wide, while less than 2000sec were needed for a range 3000T wide. The only difference is the number of primes used (10 -> 11) so I guess it's related to magic_constant now set to 32000. Can you have a look and tell us how to avoid this kind of problems. Can you possibly set magic_constant dynamically based on input parameters (kmin and kmax) or enable "-x" on the cmd-line as you mentioned before for octo.exe. Thanks.

BTW, I checked all n=67-70 to 3000T but found no new DodecaProths.

Last fiddled with by Kosmaj on 2006-01-15 at 10:26
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Old 2006-01-15, 12:05   #19
R. Gerbicz
 
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Quote:
Originally Posted by Kosmaj
I noticed a large slow-down of dodeca.exe ver. 1.0 on a large range. Have a look. Case 1:
Code:
 
n=70, kmin=15, kmax=3000000000000000, version=1.0
Using the first 10 primes to reduce the size of the sieve array
Time=1968 sec.
Case 2:
Code:
n=70, kmin=3000000000000000, kmax=10000000000000000, version=1.0
Using the first 11 primes to reduce the size of the sieve array
   Status: 0.3 percentage of the project is complete. Time thusfar: 69 sec.
OK
I'll see it. Yesterday I have not calculated this, but I thought that there will be such a problem using many primes in the sieving area ( first 11 primes means we are using primes up to 31 ). Probably this occured because we are sieving more numbers ( 12 numbers ).
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Old 2006-01-15, 13:24   #20
Kosmaj
 
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All right, thanks.

BTW, I just ran into the first DodecaProth for n=70:
14494401979227555 70 [2E16]

Note that k has 17 digits. k*2^n+/-1 members have 38, while 2^n+/-k have 22 digits. One leg on the left and one on the right.

I'm also enclosing a Pari script I use to verify DodecaProths and count legs. To use it start Pari from the folder where you saved the file, then type:
Code:
gp> read("isddp.txt")
gp> isddp(14494401979227555,70)
14494401979227555 70 is DodecaProth! ... Left_legs=1, Rigth_legs=1.
Attached Files
File Type: txt isddp.txt (630 Bytes, 280 views)
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Old 2006-01-15, 13:29   #21
Kosmaj
 
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All right, thanks.

BTW, I just ran into the first DodecaProth for n=70:
14494401979227555 70 [2E16]

Note that k has 17 digits. k*2^n+/-1 members have 38, while 2^n+/-k have 22 digits. One leg on the left and one on the right.

I'm also enclosing a Pari script I use to verify DodecaProths and count legs. To use it start Pari from the folder where you saved the file, then type:
Code:
gp> read("isddp.txt")
gp> isddp(14494401979227555,70)
14494401979227555 70 is DodecaProth! ... Left_legs=1, Rigth_legs=1.
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Old 2006-01-15, 13:44   #22
R. Gerbicz
 
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"Robert Gerbicz"
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Default New dodeca program version 2.0

This is faster than dodeca 1.0, but the speed up is very very different for different n values and ranges.

To obtain this I've eliminated almost all modular multiplications ( in the part when we see if "g" is good or not ). Now magic_constant=32000 is good for this version. I'll think what would be a good "default" value. But note that we are sieving also up to 32000 and one block length is also 32000.

Kosmaj can you test this version, I've checked only for n=44,47. And test your previous case 1 and case 2.

You can download exe for windows from: http://www.robertgerbicz.tar.hu/dodeca_2_0.exe

Or see the attachment for the c code.
Attached Files
File Type: txt dodeca_2_0.txt (14.6 KB, 227 views)

Last fiddled with by R. Gerbicz on 2006-01-15 at 13:49
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