A (left) group code of length n is a linear code which is the image of a (left) ideal of a group algebra via an isomorphism FG→ F which maps G to the standard basis of F. Many classical linear codes have been shown to be group codes. In this paper we obtain a criterion to decide when a linear code is a group code in terms of its intrinsical properties in the ambient space F, which does not assu...

Endpoint results are presented for multi-valued cyclic contraction mappings on complete metric spaces (X, d). Our results extend previous results given by Nadler (1969), Daffer-Kaneko (1995), Harandi (2010), Moradi and Kojasteh (2012) and Karapinar (2011).

In this paper, the notion of cyclic $varphi$-contraction in fuzzymetric spaces is introduced and a fixed point theorem for this typeof mapping is established. Meantime, an example is provided toillustrate this theorem. The main result shows that a self-mappingon a G-complete fuzzy metric space has a unique fixed point if itsatisfies the cyclic $varphi$-contraction. Afterwards, some results inco...

For a wide class of weights we find the approximative point spectrum and the essential spectrum of the pointwise multiplication operator Mφ, Mφ(f)=φf , on the weighted Banach spaces of analytic functions on the disc with the sup-norm. Therefore we characterize when Mφ is Fredholm or is an isomorphism into. We study also cyclic phenomena of the adjoint map M ′ φ.

Abstract: In this paper, we study ZpZp[u]-additive codes, where p is prime and u 2 = 0. In particular, we determine a Gray map from ZpZp[u] to Z α+2β p and study generator and parity check matrices for these codes. We prove that a Gray map Φ is a distance preserving map from (ZpZp[u],Gray distance) to (Z α+2β p ,Hamming distance), it is a weight preserving map as well. Furthermore we study the ...

Several classical facts due to Lyndon, Shenitzer, and Baumslag about ranks of subgroups generated by solutions to equations over the free group are generalized and given a uniform proof. Given a graph of free groups G = Γ(Fi) over cyclic subgroups and a homomorphism φ : G → F which embeds each Fi, there is a natural two complex Xφ which encodes φ. Our strategy for extracting algebraic informati...

in this paper, the notion of cyclic $varphi$-contraction in fuzzymetric spaces is introduced and a fixed point theorem for this typeof mapping is established. meantime, an example is provided toillustrate this theorem. the main result shows that a self-mappingon a g-complete fuzzy metric space has a unique fixed point if itsatisfies the cyclic $varphi$-contraction. afterwards, some results inco...

For an embedding φ of the Cuntz algebra OM into ON , OM is identified with a subalgebra φ(OM) of ON . We construct irreducible representations of ON with continuous parameters by extending irreducible representations of OM . They are not unitarily equivalent to any generalized permutative representation, especially not to any permutative representation by Bratteli-Jorgensen and Davidson-Pitts. ...

Recent results have shown that any closed operator A commuting with the backwards shift S∗ restricted to K u := H 2 ⊖ uH, where u is an inner function, can be realized as a Nevanlinna function of S∗ u := S ∗| K2 u , A = φ(S∗ u), where φ belongs to a certain class of Nevanlinna functions which depend on u. In this paper this result is generalized to show that given any contraction T of class C0(...