In this paper, we deal with some corresponding relations between knots and polynomials by using the basic properties of knot polynomials (such as, some special values of knot polynomials, the Arf invariant and derivative of knot polynomials). We give necessary and sufficient conditions that a Laurent polynomial with integer coefficients, whose breadth is less than five, is the Jones polynomial of a certain knot.
In the present paper, we compute the number of the symplectic involutions over the finite field F with charF = 2, and also one Cartesian authentication code is obtained. Furthermore, its size parameters are computed completely. If assume that the coding rules are chosen according to a uniform probability, PI and PS denote the largest probabilities of a successful impersonation attack and a successful substitution attack respectively, then PI and PS are also computed.
Let G be the finite cyclic group Z_2 and V be a vector space of dimension 2n with basis x_1,...,x_n,y_1,...,y_n over the field F with characteristic 2.If σ denotes a generator of G,we may assume that σ(x_i)= ayi,σ(y_i)= a～-1x_i,where a ∈ F.In this paper,we describe the explicit generator of the ring of modular vector invariants of F[V]～G.We prove that F[V]～G = F[l_i = x_i + ay_i,q_i = x_iy_i,1 ≤ i ≤ n,M_I = X_I + a～-I-Y_I],where I∈An = {1,2,...,n},2 ≤-I-≤ n.
