We consider a bounded version of the restrictive and the restrictive list H-coloring problem in which the number of pre-images of certain vertices of H is taken as parameter. We consider the decision and the counting versions, as well as, further variations of those problems. We provide complexity results identifying the cases when the problems are NP-complete or #P-complete or polynomial time ...

A phylogeny is a tree capturing evolution and ancestral relationships of a set of taxa (e.g., species). Reconstructing phylogenies from molecular data plays an important role in many areas of contemporary biological research. A phylogeny is perfect if (in rough terms) it correctly captures all input data. Determining if a perfect phylogeny exists was shown to be intractable in 1992 by Mike Stee...

We prove that the counting problems #1-in-3Sat, #Not-All-Equal 3Sat and #3-Colorability, whose decision counterparts have been the most frequently used in proving NP-hardness of new decision problems, are #P-complete. On one hand, the explicit #P-completeness proof of #1-in-3Sat could be useful to prove complexity results within uniication theory. On the other hand, the fact that #3-Colorabilit...

The complexity of computing the Tutte polynomial T(~/c,x,y) is determined for transversal matroid ,4s and algebraic numbers x and y. It is shown that for fixed x and y the problem of computing T(~,x,y) for JA a transversal matroid is ~pP-complete unless the numbers x and y satisfy (x 1)(y 1) = 1, in which case it is polynomial-time computable. In particular, the problem of counting bases in a t...