15A30 15B33 10 Hasse diagram 4 minimax equivalence 4 quadratic Tits form 4 similarity 4 representation 3 2-monomial matrix 2 Dynkin diagram 2 Jacobson radical 2 Kleiner's poset 2 Tits \(P\)-critical poset 2 Tits quadratic form 2 \(0\)-balanced subposet 2 \(P\)-critical poset 2 canonically \(t\)-cyclic matrix 2 commutative ring 2 defining sequence 2 direct sum of posets 2 free module 2 group 2 hereditary reducible matrix 2 indecomposable matrix 2 irreducible matrix 2 linear operator 2 local ring 2 minimax sum 2 one-side and two-side sums 2 principal poset 2 quiver 2