PRP test largely on input number

[lukerichards]

Originally Posted by axn

3^504206+3 = 3(3^504205+1).

3^504205+1 does have a few algebraic factors, but not nearly as many as the other one.

Thanks.


Last time I tackled this, I did actually partially factor the N+1 composite. I forgot how far.


http://factordb.com/index.php?query=3%5E504206%2B3


The unknown-status large factor doesn't have a neat expression for forming it though:


http://factordb.com/index.php?id=1100000001124807633

[axn]

Originally Posted by lukerichards

The unknown-status large factor doesn't have a neat expression for forming it though:


http://factordb.com/index.php?id=1100000001124807633

Check now.

[GP2]

Originally Posted by lukerichards

Have tried 3^504206+2, as well as 3^226+1. Neither work.


Am running Ubuntu 18.04 64-bit.

The program pfgw64 uses dynamically linked shared libraries. So maybe it's not finding them.

Try running ldd on the executable file and see what it tells you: ldd pfgw64

I think on RedHat-based Linuxes, ld-linux-x86-64.so.2 is found at /lib64/ld-linux-x86-64.so.2 whereas on Ubuntu it's found at /lib/x86_64-linux-gnu/ld-linux-x86-64.so.2

[lukerichards]

Originally Posted by GP2

The program pfgw64 uses dynamically linked shared libraries. So maybe it's not finding them.

Try running ldd on the executable file and see what it tells you: ldd pfgw64

I think on RedHat-based Linuxes, ld-linux-x86-64.so.2 is found at /lib64/ld-linux-x86-64.so.2 whereas on Ubuntu it's found at /lib/x86_64-linux-gnu/ld-linux-x86-64.so.2

Thanks for your advice here. I have run ldd, but the output means little to me on its own.

user1@ubuntu-upstairs:~/OpenPFGW$ ldd pfgw64
    linux-vdso.so.1 (0x00007ffd8af0b000)
    libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f9c7abb0000)
    libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007f9c7a820000)
    libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f9c7a480000)
    libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f9c7a088000)
    /lib64/ld-linux-x86-64.so.2 (0x00007f9c7add0000)
    libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007f9c79e70000)

I also have the static binary (pfgw64s) was well as the dynamic one and they both provide the same error, suggesting its possibly not a problem with dynamic links?

[paulunderwood]

Originally Posted by lukerichards

I also have the static binary (pfgw64s) was well as the dynamic one and they both provide the same error, suggesting its possibly not a problem with dynamic links?

Do you have the GMP libgmp library installed?

I get:

 ldd pfgw64
	linux-vdso.so.1 (0x00007ffe15fe1000)
	libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007ff81fb44000)
	libstdc++.so.6 => /usr/lib/x86_64-linux-gnu/libstdc++.so.6 (0x00007ff81f7c2000)
	libgmp.so.10 => /usr/lib/x86_64-linux-gnu/libgmp.so.10 (0x00007ff81f53f000)
	libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007ff81f23b000)
	libgcc_s.so.1 => /lib/x86_64-linux-gnu/libgcc_s.so.1 (0x00007ff81f024000)
	libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007ff81ec85000)
	/lib64/ld-linux-x86-64.so.2 (0x00007ff81fd61000)

[lukerichards]

Originally Posted by paulunderwood

Do you have the GMP libgmp library installed?

Nope! Installing now...

[lukerichards]

Originally Posted by lukerichards

Nope! Installing now...

#headdesk


Installed from https://gmplib.org/manual/Installing...Installing-GMP


Using latest version.


Still getting the same output from ldd.


Trying to compile using 'make' from source files on sourceforge throws this error:

g++: error: packages/gmp/64bit/libgmp.a: No such file or directory
g++: error: packages/gwnum/64bit/gwnum.a: No such file or directory

So somehow, installing gmplib hasn't had the desired effect!

[paulunderwood]

The library should be in the Ubuntu repository. Try

sudo apt-get install libgmp10

For installing GMP from source you should have run (in the source directory):

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install build-essential
./configure
make
make check
sudo make install

[lukerichards]

Originally Posted by paulunderwood

The library should be in the Ubuntu repository. Try

sudo apt-get install libgmp10

For installing GMP from source you should have run (in the source directory):

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install build-essential
./configure
make
make check
sudo make install

I did run that process exactly. And for good measure, I tried to install from apt-get and it told me I already have the latest version.


Have even tried the old favourite of 'turn it off and on again' but still getting the "Illegal instruction 'core dumped'" error.


Could it be that I need to pass pfgw an instruction to look in usr/bin for the GMP library?

[lukerichards]

And if I try to build pfgw from source files I get:

user1@ubuntu-upstairs:~/openpfgw-code-r646$ make
make -C pform/pflib
make[1]: Entering directory '/home/user1/openpfgw-code-r646/pform/pflib'
make[1]: Nothing to be done for 'all'.
make[1]: Leaving directory '/home/user1/openpfgw-code-r646/pform/pflib'
make -C pform/pfmath
make[1]: Entering directory '/home/user1/openpfgw-code-r646/pform/pfmath'
make[1]: '.libs/pfmath.a' is up to date.
make[1]: Leaving directory '/home/user1/openpfgw-code-r646/pform/pfmath'
make -C pform/pfgwlib
make[1]: Entering directory '/home/user1/openpfgw-code-r646/pform/pfgwlib'
make[1]: Nothing to be done for 'all'.
make[1]: Leaving directory '/home/user1/openpfgw-code-r646/pform/pfgwlib'
make -C pform/pfoo
make[1]: Entering directory '/home/user1/openpfgw-code-r646/pform/pfoo'
make[1]: Nothing to be done for 'all'.
make[1]: Leaving directory '/home/user1/openpfgw-code-r646/pform/pfoo'
make -C pform/pfio
make[1]: Entering directory '/home/user1/openpfgw-code-r646/pform/pfio'
make[1]: Nothing to be done for 'all'.
make[1]: Leaving directory '/home/user1/openpfgw-code-r646/pform/pfio'
make -C pform/pfgw
make[1]: Entering directory '/home/user1/openpfgw-code-r646/pform/pfgw'
make[1]: Nothing to be done for 'all'.
make[1]: Leaving directory '/home/user1/openpfgw-code-r646/pform/pfgw'
g++ -O3 -m64 -DX86_64 -D_64BIT  -I../../packages/gmp/64bit -I../../pfconfig/headers    \
    pform/pfgw/.libs/pfgw_main.a  pform/pfio/.libs/pfio.a pform/pfoo/.libs/pfoo.a pform/pfgwlib/.libs/pfgwlib.a \
    pform/pfmath/.libs/pfmath.a pform/pflib/.libs/pflib.a \
    packages/gmp/64bit/libgmp.a packages/gwnum/64bit/gwnum.a  -Wl,-no_pie -lpthread -lstdc++ -o pfgw64
g++: error: packages/gmp/64bit/libgmp.a: No such file or directory
g++: error: packages/gwnum/64bit/gwnum.a: No such file or directory
makefile:8: recipe for target 'pfgw64' failed
make: *** [pfgw64] Error 1

[Batalov]

Originally Posted by lukerichards

When I try the same input, I get:

Illegal instruction (core dumped)

Any idea what I'm doing wrong?

You will need to recompile the binary. Both static and dynamic pfgw binaries core-dump on some CPUs (but not on most others), because of the way they are compiled.

They work for most people though, so the number of complains was not enough for them to reach the maintainer.

So roll up your sleeves and build the binary from the source.

Originally Posted by lukerichards

g++: error: packages/gmp/64bit/libgmp.a: No such file or directory
g++: error: packages/gwnum/64bit/gwnum.a: No such file or directory
makefile:8: recipe for target 'pfgw64' failed
make: *** [pfgw64] Error 1

Build libgmp and gwnum, too, of course. Do you expect them to show up magically in that path?