We study whether sets inside NP can be reduced to sets with low information content but possibly still high computational complexity. Examples of sets with low information content are tally sets, sparse sets, P-selective sets and membership comparable sets. For the graph automorphism and isomorphism problems GA and GI, for the directed graph reachability problem GAP, for the determinant functio...

abstract appendiceal intussusception is a very rare cause of abdominal colic in childhood. this paper reports a reducible appendiceal intussusception in the barium enema in a girl and reviews articles in pubmed.

This paper provide a generalization of non-reducible descriptors. Non-reducible descriptors are used in supervised pattern recognition problems when the pattern descriptions consist of Boolean variables. This generalization extends the concept of distance between patterns of different classes. A mathematical model to construct generalized non-reducible descriptors, a computational procedure, an...