alpha_acyclic (775B)
1 # Alpha acyclic 2 3 Condition on [hypergraph] 4 5 On [graph_undirected], equivalent to [graph_acyclic] 6 7 Equivalent to [running_intersection_property] 8 9 Equivalent to having a [join_tree] 10 11 Equivalent to being both [hypergraph_conformal] and [hypergraph_chordal] 12 13 Equivalent to having an [alpha_elimination_order] 14 15 Equivalent to [querywidth] and [hypertreewidth] and [generalized_hypertreewidth] being 1 16 17 Defining paper proving the equivalences: [beeri1983desirability] 18 19 Can be checked on [hypergraph_reduced], i.e., hyperedges that are covered by another hyperedge do not matter 20 21 Can be tested in [linear_time] using [tarjan1984simple] via [chordal] and [hypergraph_chordal], but non-obvious 22 23 Up: [degree_of_acyclicity] 24 25 See also: [acyclic_hypergraph_sandwich_problem], [alpha_leaf]