13 citations · 54 across the 15 of their papers we have counts for
Showing 2009Show all
3 papers · 1 filter
math.OC2009★ 5 cited
Combinatorial Characterizations of K-matrices
Jan Foniok, Komei Fukuda, Lorenz Klaus
We present a number of combinatorial characterizations of K-matrices. This extends a theorem of Fiedler and Ptak on linear-algebraic characterizations of K-matrices to the setting…
math.CO2009★ 3 cited
Dualities and dual pairs in Heyting algebras
Jan Foniok, Jaroslav Nesetril, Ales Pultr +1
We extract the abstract core of finite homomorphism dualities using the techniques of Heyting algebras and (combinatorial) categories.
math.CO2009★ 3 cited
Interleaved adjoints on directed graphs
Jan Foniok, Jaroslav Nesetril, Claude Tardif
For an integer k >= 1, the k-th interlacing adjoint of a digraph G is the digraph i_k(G) with vertex-set V(G)^k, and arcs ((u_1, ..., u_k), (v_1, ..., v_k)) such that (u_i,v_i) \in…