A finite group FH is said to be Frobenius-like if it has a nontrivial nilpotent normal subgroup F with a nontrivial complement H such that [F, h] = F for all nonidentity elements h is an element of H. Suppose that a finite ...

In this paper, we investigate the three-dimensional Schrodinger operator with a periodic, relative to a lattice Omega of R(3), potential q. A special class V of the periodic potentials is constructed, which is easily and ...

We obtain uniform asymptotic formulas for the eigenvalues and eigenfunctions of the Sturm-Liouville operators L (t) (q) with a potential q a L (1)[0,1] and t-periodic boundary conditions, t a (-pi, pi]. Using these formulas, ...

In this paper we obtain asymptotic formulae of arbitrary order for the Bloch eigenvalue of the periodic Schrödinger operator -△ + q(x), of arbitrary dimension, when the corresponding quasi-momentum lies near planes of diffraction.

In this article we obtain asymptotic formulas of arbitrary order for eigenfunctions and eigenvalues of the nonselfadjoint Sturm-Liouville operators with Dirichlet boundary conditions, when the potential is a summable ...

We obtain asymptotic formulas with arbitrary order of accuracy for the eigenvalues and eigenfunctions of a nonselfadjoint ordinary differential operator of order n whose coefficients are Lebesgue integrable on [0,1] and ...

Let R be a ring with identity and I(X, R) be the incidence algebra of a locally finite partially ordered set X over R. In this article, we investigate the necessary and sufficient conditions for the incidence ring to be ...

In this paper, we classify all finite groups satisfying the following property: their conjugacy class lengths are set-wise relatively prime for any six distinct classes.

Any finite dimensional semisimple algebra A over a field K is isomorphic to a direct sum of finite dimensional full matrix rings over suitable division rings. We shall consider the direct sum of finite dimensional full ...

In 1970, Yano, [1], studied Riemannian manifolds which admit semisymmetric metric connections whose curvature tensors vanish (see also [2]). The properties of a Riemannian manifold admitting a semi-symmetric metric connection ...