Thanks Michael,
https://packages.debian.org/stable/allpackages?format=txt.gz https://packages.debian.org/oldstable/allpackages?format=txt.gz https://packages.debian.org/testing/allpackages?format=txt.gz https://packages.debian.org/jessie/allpackages?format=txt.gz
(goto https://packages.debian.org/stable/, select a version at the top and click at the end on "(compact compressed textlist)")
Looks like you've got a sizable amount of data here.
I guess there are similar lists for the other major distros.
It should take only a few lines of Python to fetch and check these.
What are the relevant distros?
Ubuntu (this covers A LOT of distros) Mint Fedora Debian openSUSE Arch / Manjaro (although arch is fairly bleeding edge)
That most of the targets. We'd first have to get a sensible read on supported versions vs bleeding edge and their relevant dates.
Only then could we calculate the packages we need.
Best Regards, Martin Owens