In this paper, we introduce and study the prime, strongly prime,semiprime and irreducible fuzzy bi-ideals of a semigroup. We characterize thosesemigroups for which each fuzzy bi-ideal is semiprime. We also characterizethose semigroups for which each fuzzy bi-ideal is strongly prime.

The magnetoresistivity of a disordered metallic system is derived using the a2KF-scatteringo theory in terms of a generalized Boltzmann equation with magnetic field B included. The behaviour is complex but in the limit of weak fields (which are experimentally quite strong) we find a negative contribution to the relaxation time proportional to B which gives rise to a positive magnetoconductivity...

In this paper we establish some new congruences involving central binomial coefficients as well as Catalan numbers. Let p be a prime and let a be any positive integer. We determine ∑pa−1 k=0 ( 2k k+d ) mod p2 for d = 0, . . . , pa and ∑pa−1 k=0 ( 2k k+δ ) mod p3 for δ = 0, 1. We also show that

Suppose xm+axn is a permutation polynomial over Fp, where p > 5 is prime and m > n > 0 and a ∈ Fp. We prove that gcd(m−n, p−1) / ∈ {2, 4}. In the special case that either (p− 1)/2 or (p− 1)/4 is prime, this was conjectured in a recent paper by Masuda, Panario and Wang.

Let E/Q be an elliptic curve of conductor N without complex multiplication and let K be an imaginary quadratic field of discriminant D prime to N . Assume that the number of primes dividing N and inert in K is odd, and let Hc be the ring class field of K of conductor c prime to ND with Galois group Gc over K. Fix a complex character χ of Gc. Our main result is that if LK(E,χ, 1) 6= 0 then Selp(...

We study classical solutions (ic–instantons) in N = 4 SYM in 4D which, in the strong coupling limit, correspond to complex two–dimensional manifolds. Asymptotically in time the latter have boundaries represented by compact real three–manifolds. Therefore they lend themselves to an interpretation in terms of 3–brane scattering. We suggest that these solutions may represent scattering of D3–brane...

Let D ≡ 7 mod 8 be a positive squarefree integer, and let hD be the ideal class number of ED = Q( √−D). Let d ≡ 1 mod 4 be a squarefree integer relatively prime to D. Then for any integer k ≥ 0 there is a constant M = M(k), independent of the pair (D, d), such that if (−1)k = sign(d), (2k + 1, hD) = 1, and √ D > 12 π d(log |d|+ M(k)), then the central L-value L(k + 1, χ D,d ) > 0. Furthermore, ...

Let $A$ be a Noetherian ring, $I$ be an ideal of $A$ and $sigma$ be a semi-prime operation, different from the identity map on the set of all ideals of $A$. Results of Essan proved that the sets of associated prime ideals of $sigma(I^n)$, which denoted by $Ass(A/sigma(I^n))$, stabilize to $A_{sigma}(I)$. We give some properties of the sets $S^{sigma}_{n}(I)=Ass(A/sigma(I^n))setminus A_{sigma}(I...

A ring $A$ is (principally) nilary, denoted (pr-)nilary, if whenever $XY=0,$ then there exists a positive integer $n$ such that either $X^n=0$ or $Y^n=0$ for all (principal) ideals $X$, $Y$ of $A$. We determine necessary and/or sufficient conditions the group $A[G]$ to be nilary in terms on $G$. For example, we show that: (1) If (pr-)nilary and $G$ prime order each finite nontrivial normal subg...