As stated by the previous poster, the \102 \103 etc are octal codes. These can be looked up in an ascii table such as: this one.

Also as stated, since it is octal, it is a base 8 system, meaning the numbering goes:

000 001 002 003 004 005 006 007
010 011 012 013 014 015 016 017
020 021 022 023 024 025 026 027
etc
etc