Hello. I am accessing this paper:

http://pubs.rsc.org/en/content/articlepdf/2005/cp/b508541a

wherein I see notation such as: 

Rb, Sr, Cs Ba: (8s8p5d)/[7s5p3d]

I believe this is related to Dunning notation for basis sets, which I am unsure of.

Questions:

What does the "/" mean, in particular the relation of the basis left of "/" to the basis set right of "/"?

How does one know how many primitive Gaussians are being used for eg. 8 s-functions from the example above?

What does "decontract" mean? I read this in the following sentence:

"For Y–Rh we have only added one p set and decontracted the s yielding (7s7p5d)/[6s4p3d]"

Thank you so much for your time and advice. Links are also welcome if preferred!