Let R be a Krull ring with quotient field K and a1, . . . , an in R. If and only if the ai are pairwise incongruent mod every height 1 prime ideal of infinite index in R does there exist for all values b1, . . . , bn in R an interpolating integer-valued polynomial, i.e., an f ∈ K[x] with f(ai) = bi and f(R) ⊆ R. If S is an infinite subring of a discrete valuation ring Rv with quotient field K a...

A polynomial, A(z), can be represented by a polynomial residue system and, given enough independent residues, the polynomial can be reconstituted from its residues by the Chinese remainder theorem (CRT). A special case occurs when the discrete Fourier transform and its inverse realise the residue evaluations and CRT respectively, in which case the residue system is realised by the action of a m...

Let α(G) be the stability number of a graph G. A class of graphs P is called α-polynomial if there exists a polynomial-time algorithm to determine α(G) for G ∈ P. For every hereditary α-polynomial class P we construct a hereditary extension of P which is either an α-polynomial class or α can be approximated in polynomial time in the extended class.