After being a while on Brilliant, I realize a lot of the problems in the number theory and combinatorics sections contain math which I do not know.
I've always glimpsed at books or lectures which include the traditional mathematical symbols (For all, There exists, etc.) where proofs are formulated.
I'd like to know what the area of mathematics that deals with an introduction to proof and using all those symbols in number theory and combinatorics, with some traditional and theoretical mathematics.
I have a math exercise book in which a lot of the problems say "Prove..." and I have no clue what do in these cases because I certainly have know knowledge in this vast area of mathematics.
Can anyone please give me resources (books, lectures, videos, notes) such that I can try to get an introduction over the summer.