Perepechko, A. Yu.
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Mathematical Notes

Abstract Affine algebraic surfaces of Markov type of the form \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$x^2+y^2+z^2-xyz=c$$\end{document} are studied. Their autom...

Bogachev, V. I. Doledenok, A. N. Malofeev, I. I.
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Mathematical Notes

Vorob’ev, N. T. Lantsetova, E. D.
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Mathematical Notes

Abstract It is proved that the lattice of all Fitting classes of finite groups is not distributive, and conditions under which Fitting classes satisfy the distributive and modular laws are determined.

Novikov, I. V.
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Mathematical Notes

Abstract Assume that a polygon is composed of equal rectangles. We find all quadratic irrationalities \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$r$$\end{document} ...

Bolotin, S. V.
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Mathematical Notes

Avakov, E. R. Magaril-Il’yaev, G. G.
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Mathematical Notes

Al-Shomrani, M. Mosa Salah, M. Ben Mohamed Ghanmi, A. Kefi, K.
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Mathematical Notes

Abstract This paper deals with the existence of a solution of a problem involving Leray–Lions type operators in Sobolev spaces with variable exponent. The proofs of our main results combine variational methods with energy estimates and Ekeland’s variational principle. This paper improves and generalizes previous ones in literature, more precisely t...

Gorbunov, I. A.
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Mathematical Notes

Abstract For any propositional logic, Sushko’s lemma states that, for any substitution, the preimage of the set of all tautologies of this logic is its theory. The problem of the relationship between the set of all such preimages and the set of all theories for classical propositional logic is considered. It is proved that any consistent theory of ...

Gaisin, R. A.
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Mathematical Notes

Abstract Problems of constructing regular majorants for sequences \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\mu=\{\mu_n\}_{n=0}^{\infty}$$\end{document} of number...

Tyulenev, A. I.
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Mathematical Notes