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2023-04-04, 19:30   #1101
rogue

"Mark"
Apr 2003
Between here and the

7,487 Posts

Quote:
 Originally Posted by storm5510 You don't understand the question. OK. I will make it simpler. Is k=1e6 the same as n=1e6?
Yes. All numeric inputs support scientific notation. They also support "g" and "m" and a few other characters.

2023-04-04, 23:23   #1102
storm5510
Random Account

Aug 2009
Oceanus Procellarum

BE116 Posts

Quote:
 Originally Posted by rogue Yes. All numeric inputs support scientific notation. They also support "g" and "m" and a few other characters.
I think you're still missing the question. Is k=10000 in fbncsieve equivalent to n=10000 in srsieve2? I was told quite a few years ago that a small n value was some gigantic number when converted to k.

I don't know how else to word this...

2023-04-05, 00:02   #1103
gd_barnes

"Gary"
May 2007
Overland Park, KS

1256910 Posts

Quote:
 Originally Posted by storm5510 I think you're still missing the question. Is k=10000 in fbncsieve equivalent to n=10000 in srsieve2? I was told quite a few years ago that a small n value was some gigantic number when converted to k. I don't know how else to word this...
Why would the multiplier be equivalent to the exponent when talking about k*b^n-1 (or +1) forms? Since both fbncsieve and srsieve2 sieve those specific forms, the question comes across as not making sense.

Fbncsieve sieves a wide range of k. Srsieve2 sieves a wide range of n. Is that what you are asking?

To answer your question: no. They are not equivalent. 3*2^10000-1 is not the same as 10000*2^3-1. I'm not sure why the question had to be asked. The calculator in Windows would have given the answer.

Last fiddled with by gd_barnes on 2023-04-05 at 00:08

2023-04-05, 00:46   #1104
storm5510
Random Account

Aug 2009
Oceanus Procellarum

3,041 Posts

Quote:
 Originally Posted by gd_barnes Why would the multiplier be equivalent to the exponent when talking about k*b^n-1 (or +1) forms? Since both fbncsieve and srsieve2 sieve those specific forms, the question comes across as not making sense. Fbncsieve sieves a wide range of k. Srsieve2 sieves a wide range of n. Is that what you are asking?
No. It is not about ranges. There is a conversion for decimal to binary. Both can be the same number, just expressed in different ways. Example: n could be 15,383 and its equivalent k could be 584,101. It's like comparing pennies to $1 paper bills. Both the same value, but don't look the same. I will let this go. It is not important. I was just goofing to pass some time. 2023-04-05, 04:04 #1105 Citrix Jun 2003 163110 Posts Quote:  Originally Posted by rogue For base 2, even k are already removed, so you don't need -r. I broke this in 1.6. I will fix the code. I think I should remove -r and do that automatically. Thoughts? I would prefer having a -r option or if -r is present by default then an include option. 2023-04-05, 12:40 #1106 rogue "Mark" Apr 2003 Between here and the 11101001111112 Posts Quote:  Originally Posted by storm5510 Example: n could be 15,383 and its equivalent k could be 584,101. It's like comparing pennies to$1 paper bills. Both the same value, but don't look the same.
This doesn't make any sense to me so I don't think you are asking the right question.

Both sieves sieve k*b^n+/-1, but fbncsieve sieves for a fixed n and variable k (expressed as a range using -k and -K). srsieve2 sieves on variable n (expressed as a range using -n and -N) for one or more k (expressed as a sequence, e.g. k*b^n+/-1)

For srsieve2 -n1e6 -N2e6 means that variable n has a value between 1000000 to 2000000.
For fbncsieve -k1e6 -K2e6 means that variable k has a value between 1000000 to 2000000.

 2023-04-05, 13:18 #1107 henryzz Just call me Henry     "David" Sep 2007 Liverpool (GMT/BST) 23×271 Posts Is he referring to something like 1024*2^n-1 == 2^(n+10)-1 ?
2023-04-05, 13:59   #1108
storm5510
Random Account

Aug 2009
Oceanus Procellarum

3,041 Posts

Quote:
 Originally Posted by rogue This doesn't make any sense to me so I don't think you are asking the right question. Both sieves sieve k*b^n+/-1, but fbncsieve sieves for a fixed n and variable k (expressed as a range using -k and -K). srsieve2 sieves on variable n (expressed as a range using -n and -N) for one or more k (expressed as a sequence, e.g. k*b^n+/-1) For srsieve2 -n1e6 -N2e6 means that variable n has a value between 1000000 to 2000000. For fbncsieve -k1e6 -K2e6 means that variable k has a value between 1000000 to 2000000.

The highlighted above is exactly what I was looking for. Both are numerically weighted the same. It would appear that I was being led-by-the-nose years ago when I was told they were not.

Many thanks, and apologies for the confusion!

 2023-04-06, 17:04 #1109 storm5510 Random Account     Aug 2009 Oceanus Procellarum 3,041 Posts The error below happens with an inline series, but not with an "abcd" input file. Example: Code: fbncsieve -k 3 -K 1000000 -p 3 -P 1e10 -W 6 -s "k*1061955^6+1" -o 1e10.abcd Result: Code: fbncsieve v1.6, a program to find factors of k*b^n+c numbers for fixed b, n, and c and variable k Sieve started: 3 < p < 1e10 with 499999 terms (3 < k < 1000000, k*1061955^6+1) (expecting 476143 factors) Increasing worksize to 400000 since each chunk is tested in less than a second Increasing worksize to 10000000 since each chunk is tested in less than a second Increasing worksize to 50000000 since each chunk is tested in less than a second Sieve completed at p=10171501019. CPU time: 52.31 sec. (2.78 sieving) (4.89 cores) Fatal Error: Something is wrong. Counted terms (26337) != expected terms (26336) If I repeat the example line, the counted and expected terms on the bottom line are different each time. The same occurs if I change the series in the example line. Sorry!
2023-04-06, 17:14   #1110
rogue

"Mark"
Apr 2003
Between here and the

164778 Posts

Quote:
 Originally Posted by storm5510 The error below happens with an inline series, but not with an "abcd" input file. Example: Code: fbncsieve -k 3 -K 1000000 -p 3 -P 1e10 -W 6 -s "k*1061955^6+1" -o 1e10.abcd Result: Code: fbncsieve v1.6, a program to find factors of k*b^n+c numbers for fixed b, n, and c and variable k Sieve started: 3 < p < 1e10 with 499999 terms (3 < k < 1000000, k*1061955^6+1) (expecting 476143 factors) Increasing worksize to 400000 since each chunk is tested in less than a second Increasing worksize to 10000000 since each chunk is tested in less than a second Increasing worksize to 50000000 since each chunk is tested in less than a second Sieve completed at p=10171501019. CPU time: 52.31 sec. (2.78 sieving) (4.89 cores) Fatal Error: Something is wrong. Counted terms (26337) != expected terms (26336) If I repeat the example line, the counted and expected terms on the bottom line are different each time. The same occurs if I change the series in the example line. Sorry!
I will take a look. It shouldn't be too hard to fix.

2023-04-07, 15:19   #1111
rogue

"Mark"
Apr 2003
Between here and the

7,487 Posts

Quote:
 Originally Posted by rogue I will take a look. It shouldn't be too hard to fix.
The code is fixed and commited to sourceforge. This happens only with ABCD formatted output files.

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