When I browse http://dev-builds.libreoffice.org/daily/ trying to find a version to test. I find many versions with number like 45-TDF 46-TDF 70-TDF 42-TDF 39-TDF
I know TDF means the document foundation but what about the numbers?
I wonder what does it stand for and how to know which one is suitable for me.
As I understand it the number is simply an internal code for the particular machine on which the build is built, thus it corresponds to platform + architecture. It can be effectively ignored unless you are concerned with development / infrastructure.
EDIT: To expand on what I initially wrote, it appears these are Tinderbox numbers. Wiki page here.