generate-profile.pl error with error while loading shared libraries: libg2c.so.0:

Dear I-TASSER team:

I am working on ubuntu 16.04. When I tried to run generate_profile.pl for example pdb in update_IT_lib/pdb , there was worng with my update.
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Here is the command & the wrong information:
./generate_profile.pl -blastdir /home/rsl/I-TASSER5.1/blast -nrdir /home/xxxx/ITLIB/nr -pkgdir /home/xxxxx/I-TASSER5.1/update_IT_lib/ -newdir /home/xxxx/ITLIB/PDB -PDBdir /home/xxxx/I-TASSER5.1/update_IT_lib/pdb -list list

then after solving many issues, finally i am getting this message:

1. Prepare list...
Number of templates in list: 2

2. Check PDB file...
Number of templates to be added: 2

3. Generate AAA.seq and AAA.sec...
4u65A
4u65E

4. Generate profiles for non-homologous chains...
DEP for 1/2, 4u65A
DEP for 2/2, 4u65E

MTX for 1/2, 4u65A
MTX for 2/2, 4u65E

CNT for 1/2, 4u65A
CNT for 2/2, 4u65E

SIG
/home/xxxxxx/I-TASSER5.1/update_IT_lib/sig: error while loading shared libraries: libg2c.so.0: cannot open shared object file: No such file or directory
chmod: cannot access '4u65A.sig': No such file or directory
mv: cannot stat '4u65A.sig': No such file or directory
chmod: cannot access '/home/xxxxxx/ITLIB/PDB/SIG/4u65A.sig': No such file or directory
chmod: cannot access '4u65E.sig': No such file or directory
mv: cannot stat '4u65E.sig': No such file or directory
chmod: cannot access '/home/xxxxx/ITLIB/PDB/SIG/4u65E.sig': No such file or directory

dotProfile for 1/2, 4u65A
dotProfile for 2/2, 4u65E

stride for 1/2, 4u65A
stride for 2/2, 4u65E

5. AAA.*...

6 Check update...
checking library...
/home/xxxxx/ITLIB/PDB/DEP/4u65A.dep missed
/home/xxxxxx/ITLIB/PDB/SIG/4u65A.sig missed
/home/xxxxxx/ITLIB/PDB/DEP/4u65E.dep missed
/home/xxxxxxxx/ITLIB/PDB/SIG/4u65E.sig missed
Something is wrong with your update (see the information above)
Please re-run generate_profile.pl

I tried to find libg2c.so.0 file, it was not there. I also tried to install compat-libf2c-34.x86_64 but it is not available online. Please suggest possible solution for the error shown above.