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Hyperbolicity cones are convex algebraic cones arising from hyperbolic polynomials. A well-understood subclass of hyperbolicity cones is that of spectrahedral cones and it is conjectured that every hyperbolicity cone is spectrahedral. In this paper we prove a weaker version of this conjecture by showing that every smooth hyperbolicity cone is the linear projection of a spectrahedral cone, that is, a spectrahedral shadow. [ABSTRACT FROM AUTHOR]

In this paper, we find coefficient estimates by a new method making use of the Faber polynomial expansions for a comprehensive subclass of analytic bi-univalent functions, which is defined by subordinations in the open unit disk. The coefficient bounds presented in this paper would generalize and improve some recent works appeared in the literature. [ABSTRACT FROM AUTHOR]

The domination polynomial of a graph is the polynomial whose coefficients count the number of dominating sets of each cardinality. A recent question asks which graphs are uniquely determined (up to isomorphism) by their domination polynomial. In this paper, we completely describe the complete $$r$$ -partite graphs which are; in the bipartite case, this settles in the affirmative a conjecture of Aalipour et al. (Ars Comb, ). [ABSTRACT FROM AUTHOR]

In this paper we study some generalized versions of a recent result due to Covert, Koh, and Pi (2015). More precisely, we prove that if a subset E in a regular variety satisfies | E | ≫ q d − 1 2 + 1 k − 1 , then Δ k , F ( E ) : = { F ( x 1 + ⋯ + x k ) : x i ∈ E , 1 ≤ i ≤ k } ⊇ F q ∖ { 0 } , for some certain families of polynomials F ( x ) ∈ F q [ x 1 , … , x d ] . [ABSTRACT FROM AUTHOR]

Let F q denote the finite field of order q . In this paper, we present four new classes of permutation trinomials of the form x r h ( x 2 m − 1 ) over F 2 2 m . [ABSTRACT FROM AUTHOR]

We investigate the effect of Ito noise on the stability of stationary solutions to a class of semilinear degenerate parabolic equations with the nonlinearity satisfying an arbitrary polynomial growth condition. We will show that an Ito noise of sufficient intensity will stabilize the unstable stationary solution. [ABSTRACT FROM AUTHOR]

This paper contains two new projection theorems in the plane. First, let K ⊂ B ( 0 , 1 ) ⊂ R 2 be a set with H ∞ 1 ( K ) ∼ 1 , and write π e ( K ) for the orthogonal projection of K into the line spanned by e ∈ S 1 . For 1 / 2 ≤ s < 1 , write E s : = { e : N ( π e ( K ) , δ ) ≤ δ − s } , where N ( A , r ) is the r -covering number of the set A . It is well-known – and essentially due to R. Kaufman – that N ( E s , δ ) ⪅ δ − s . Using the polynomial method, I prove that N ( E s , r ) ⪅ min ⁡ { δ − s ( δ r ) 1 / 2 , r − 1 } , δ ≤ r ≤ 1 . I construct examples showing that the exponents in the bound are sharp for δ ≤ r ≤ δ s . The second theorem concerns projections of 1-Ahlfors–David regular sets. Let A ≥ 1 and 1 / 2 ≤ s < 1 be given. I prove that, for p = p ( A , s ) ∈ N large enough, the finite set of unit vectors S p : = { e 2 π i k / p : 0 ≤ k < p } has the following property. If K ⊂ B ( 0 , 1 ) is non-empty and 1-Ahlfors–David regular with regularity constant at most A , then 1 p ∑ e ∈ S p N ( π e ( K ) , δ ) ≥ δ − s for all small enough δ > 0 . In particular, dim ‾ B π e ( K ) ≥ s for some e ∈ S p . [ABSTRACT FROM AUTHOR]

A polyomino graph P is a connected finite subgraph of the infinite plane grid such that each finite face is surrounded by a regular square of side length one and each edge belongs to at least one square. A dimer covering of P corresponds to a perfect matching. Different dimer coverings can interact via an alternating cycle (or square) with respect to them. A set of disjoint squares of P is a resonant set if P has a perfect matching M so that each one of those squares is M-alternating. In this paper, we show that if K is a maximum resonant set of P, then P - K has a unique perfect matching. We further prove that the maximum forcing number of a polyomino graph is equal to the cardinality of a maximum resonant set. This confirms a conjecture of Xu et al. [26]. We also show that if K is a maximal alternating set of P, then P - K has a unique perfect matching. [ABSTRACT FROM AUTHOR]

The purpose of this paper is twofold. Firstly we investigate the distribution, simplicity and monotonicity of the zeros around the unit circle and real line of the real self-reciprocal polynomials R n ( λ ) ( z ) = 1 + λ ( z + z 2 + ⋯ + z n − 1 ) + z n , n ≥ 2 and λ ∈ R . Secondly, as an application of the first results we give necessary and sufficient conditions to guarantee that all zeros of the self-reciprocal polynomials S n ( λ ) ( z ) = ∑ k = 0 n s n , k ( λ ) z k , n ≥ 2 , with s n , 0 ( λ ) = s n , n ( λ ) = 1 , s n , n − k ( λ ) = s n , k ( λ ) = 1 + k λ , k = 1 , 2 , … , ⌊ n / 2 ⌋ when n is odd, and s n , n − k ( λ ) = s n , k ( λ ) = 1 + k λ , k = 1 , 2 , … , n / 2 − 1 , s n , n / 2 ( λ ) = ( n / 2 ) λ when n is even, lie on the unit circle, solving then an open problem given by Kim and Park in 2008. [ABSTRACT FROM AUTHOR]

Let K = { k 1 , k 2 , … , k r } and L = { l 1 , l 2 , … , l s } be disjoint subsets of { 0 , 1 , ⋯ p − 1 } , where p is a prime and F = { F 1 , F 2 , … , F m } be a family of subsets of [ n ] such that | F i | (mod p ) ∈ K for all F i ∈ F and | F i ∩ F j | (mod p ) ∈ L for i ≠ j . In 1991 Alon, Babai and Suzuki conjectured that if n ≥ s + max 1 ≤ i ≤ r k i , then | F | ≤ n s + n s − 1 + ⋯ + n s − r + 1 . In this paper we prove this conjecture. [ABSTRACT FROM AUTHOR]

A hyperbinary expansion of a positive integer n is a partition of n into powers of 2 in which each part appears at most twice. In this paper, we consider a generalization of this concept and a certain statistic on the corresponding set of expansions of n. We then define q-generalized m-ary trees whose vertices are labeled by ratios of two consecutive terms within the sequence of distribution polynomials for the aforementioned statistic. When m = 2, we obtain a variant of a previously considered q-Calkin-Wilf tree. [ABSTRACT FROM AUTHOR]

We construct a compact nowhere dense subset K of the closed unit disk D in the complex plane C such that R(K) = C(K) and bounded point evaluations for Pt(dA|K), 1 ≤ t < ∞, is the open unit disk D. In fact, there exists C = C(t) > 0 such that ... for 1 ≤ t < ∞ and all polynomials p. [ABSTRACT FROM AUTHOR]

We show that the techniques for resource control that have been developed by the so-called light logics can be fruitfully applied also to process algebras. In particular, we present a restriction of higher-order π-calculus inspired by soft linear logic. We prove that any soft process terminates in polynomial time. We argue that the class of soft processes may be naturally enlarged so that interesting processes are expressible, still maintaining the polynomial bound on executions. [ABSTRACT FROM AUTHOR]

We discuss computability of impressions of prime ends of compact sets. In particular, we construct quadratic Julia sets which possess explicitly described non-computable impressions. [ABSTRACT FROM AUTHOR]

The restricted parameter range set cover problem is a weak form of the NP-hard set cover problem with the restricted range of parameters. We give a polynomial time algorithm for this problem by lattices. [ABSTRACT FROM AUTHOR]

We introduce the odd Jones-Kauffman polynomial and odd Miyazawa polynomials of virtual link diagrams by using the parity of virtual link diagrams given in [Y. H. Im and K. I. Park, A parity and a multi-variable polynomial invariant for virtual links, J. Knot Theory Ramifications 22(13) (2013), Article ID: 1350073, 18pp.], which are different from the original Jones-Kauffman and Miyazawa polynomials. Also, we give a family of parities and odd polynomials for virtual knots so that many virtual knots can be distinguished. [ABSTRACT FROM AUTHOR]

Ifkis a field of characteristic zero,c ∈ k∖{0},s,t ≥ 1, andr ≥ 0 are integers, then it is shown that thek-derivationyr∂x + (ysxt + c)∂yof the polynomial algebrak[x,y] is simple. [ABSTRACT FROM PUBLISHER]

In this article, we develop the theory of SAGBI bases in G-algebras and create a criterion through which we can check if a set of polynomials in a G-algebra is a SAGBI basis or not. Moreover, we will construct an algorithm to compute SAGBI bases from a subset of polynomials contained in a subalgebra of a G-algebra. [ABSTRACT FROM AUTHOR]