@MartinSleziak The title was edited by David Roberts. The tags are still the same. mathoverflow.net/posts/332509/revisions

Although it is possible that quite a few of them get eventually deleted - four of them are closed/on hold: summarizing the kernel and nilpotent element of 0, Solve recursion with characteristic polynomial (cross-post), Combinatorics + recurrent relations question (Discrete Mathematics) and ...

...MacLane–Birkhoff's “Algebra” vs Jacobson's “Basic Algebra I,II” vs Lang's “Algebra” (also cross-post).