I'm looking for open books on abstract algebra, other than Judson's AATA. I want one with a good number of exercises (and solutions, preferably), this one covers the rest. Does anyone know of one?
This and this are similar questions. The first one has many answers and the second is markedly different, but answers specific to abstract algebra, with brief descriptions of each book (too much to expect in the first) might help someone someday.
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This builds on Viktor Vaughn's comment: Margaret Morrow's notes (PDF, 130 KB and free) in the Journal of Inquiry Based Learning introduce group theory with a sequence of directed questions. Rings and Fields are not covered.
I think this would be a great introduction, but it might help to skim through each section from another text after going through it in the notes, for a cheesy coverage of the motivation and intuition. These don't have solutions or 'hard' questions, but the solutions can be found in any standard text.
I suggest going through examples of groups after the first section - it will help later.
I have read and really enjoyed John Fraleigh's book "A First Course In Abstract Algebra". It was very reader friendly and helped me understand deeply a lot of the fundamental concepts of abstract algebra. You can find it for free here: A first course in abstract algebra