An R-module M is called epi-retractable if every submodule of MR is a homomorphic image of M. It is shown that if R is a right perfect ring, then every projective slightly compressible module MR is epi-retractable. If R is a Noetherian ring, then every epi-retractable right R-module has direct sum of uniform submodules. If endomorphism ring of a module MR is von-Neumann regular, then M is semi-...

The theorem of Ax says that any regular selfmapping of a complex algebraic variety is either surjective or non-injective; this property is called surjunctivity and investigated in the present paper in the category of proregular mappings of proalgebraic spaces. We show that such maps are surjunctive if they commute with sufficiently large automorphism groups. Of particular interest is the case o...

Minimal linear codes have diverse applications in many areas such as secret sharing schemes and secure two-party computation. There are several construction methods for these codes, one of which is based on functions over finite fields. In this paper, to construct minimal with few weights, we make use weakly regular plateaued balanced Fp, where p an odd prime, the second generic method. We obta...

In this paper, we classify all commutative weakly distance-regular digraphs of girth g and one type arcs under the assumption that \(p_{(1,g-1),(1,g-1)}^{(2,g-2)}\ge k_{1,g-1}-2\). consequence, Yang et al. (J Comb Theory Ser A 160:288–315, 2018, Theorem 1.1) is partially generalized by our result.

A weakly-connected dominating set, W, of a graph, G, is a dominating set such that the subgraph consisting of V (G) and all edges incident with vertices in W is connected. Finding a small weaklyconnected dominating set of a graph has important applications in clustering mobile ad-hoc networks. In this paper we introduce several new randomised greedy algorithms for finding small weakly-connected...