14 Answers votes newest views recent 12Do good math jokes exist? 12Sexy vacuity … 9Most harmful heuristic? 5Most helpful heuristic? 3Why is the gradient normal? 3Conjugacy classes in finite groups that remain conjugacy classes when restricted to proper subgroups 3Has anyone studied the applications which map open sets to either open or closed sets? 3Minimal basis of set of positive integers 3Ways to Synthesize Topics in Linear Algebra 3How to sufficiently motivate organization of proofs in math books 2“negative” vs “minus” 2Number of metric spaces on N points 2Is there a theorem that says that there is always more than one way to “continue a finite sequence”? 0Does every finitely generated group have a maximal normal subgroup?