mtsieve

[pinhodecarlos]

Was just wondering if I need net framework turned on since on this machine almost windows services are off. Tried the xyy siever and had the same behaviour, nothing happens.

[rogue]

Originally Posted by pinhodecarlos

Was just wondering if I need net framework turned on since on this machine almost windows services are off. Tried the xyy siever and had the same behaviour, nothing happens.

That is very odd. I build with mingw64 and link libraries as static so you shouldn't need other dlls to run the code. If it needed a dll, it was squawk at you.

Can you install mingw64 on that machine and build?

[pinhodecarlos]

Originally Posted by rogue

That is very odd. I build with mingw64 and link libraries as static so you shouldn't need other dlls to run the code. If it needed a dll, it was squawk at you.

Can you install mingw64 on that machine and build?

I’ll try it this weekend. Thank you.

[ATH]

Using the precompiled "fbncsieve.exe" v1.3.3 from mtsieve 1.8.3:

The line:
fbncsieve.exe -k 1000000001 -K 2000000000 -s "k*20000038^1+1"

fails with:
Fatal Error: 1771575385*20000038^1+1 mod 200000201 = 11167534

It works for other intervals of k.

[rogue]

Originally Posted by ATH

Using the precompiled "fbncsieve.exe" v1.3.3 from mtsieve 1.8.3:

The line:
fbncsieve.exe -k 1000000001 -K 2000000000 -s "k*20000038^1+1"

fails with:
Fatal Error: 1771575385*20000038^1+1 mod 200000201 = 11167534

It works for other intervals of k.

The problem is that it should have stopped at 200000190 and 200000201 is greater than that value. I'll have to add a check to handle that. The is that it should stop sieving at about sqrt(1771575385*20000038).

[rogue]

I have posted mtsieve 1.8.4 on the website. It addresses the following items:

   Added the new Mersenne Prime to dmdsieve.
   Fixed an issue in twinsieve and fbncsieve where it can exit with an error when
   testing primes above sqrt(max term).
   Fixed an issue (impacting all sieves) in computing the factor rate.  The issue will manifest itself by
   outputting a large factor removal rate.  It only occurs after running the sieve continuously for 5 days.

[rogue]

I realized that I forgot to fix the link on my page. It is fixed now.

[Dylan14]

I believe there is a bug with fkbnsieve. I issued the following command to a command prompt:

fkbnsieve -W 2 -P 1e9 -c 1 -C 1e6 -s "2*11^75000"

which should find factors for numbers of the form 2*11^75000+c for c in the set {1,1e6}. The sieve finishes in a few seconds and generates the following sieve file (saved as k2_n11_n75000+c.pfgw):

ABCD 2*11^75000$a [41] // Sieved to 1000000009
+10
+50
+10
+14
+54
+60
+12
+54
+4
+68
[and so on...]

I then put this file as input to pfgw, and I expect that the first number that it should test is 2*11^75000+41. However, instead I get

C:\Users\Dylan_000\Desktop\Carol-Kynea\pfgw_win_3.8.3>pfgw64 "k2_b11_n75000+c.pfgw"
PFGW Version 3.8.3.64BIT.20161203.Win_Dev [GWNUM 28.6]

Recognized ABCD Sieve file:
ABCD File
PRP: 2*11^7500041 1/25945879
^C Handler Routine called, shutting down program

which is not right. Also it seems like c = 0 is not a valid number for the -c flag, since I get the following message when I replace -c 1 to -c 0 in the first command line:

Fatal Error:  kmin must be specified

This is on the last version of mtsieve (v1.8.4).

[ATH]

There is just a + missing in the .pfgw file:

ABCD 2*11^75000+$a [41] // Sieved to 1000000009

[Dylan14]

Originally Posted by ATH

There is just a + missing in the .pfgw file:

ABCD 2*11^75000+$a [41] // Sieved to 1000000009

That is the ticket. Also I have the fix: in line 283 of FixedKBNApp.cpp change

fprintf(termsFile, "ABCD %" PRIu64"*%u^%u$a [%" PRId64"] // Sieved to %" PRIu64"\n", il_K, ii_Base, ii_N, c, largestPrime);

to

fprintf(termsFile, "ABCD %" PRIu64"*%u^%u+$a [%" PRId64"] // Sieved to %" PRIu64"\n", il_K, ii_Base, ii_N, c, largestPrime);

Also, in lines 98, 101 and 104, instead of kmin and kmax, it should be cmin and cmax.

[rogue]

Thanks for the report. I'll fix the code base.