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arXiv · 2212.02063

Classification of semidiscrete hyperbolic type equations. The case of third order symmetries

R. N. Garifullin
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Abstract

In this paper, a classification of semidiscrete equations of hyperbolic type is carried out. We study the class of equations of the form $$\frac{du_{n+1}}{dx}=f\left(\frac{du_{n}}{dx},u_{n+1},u_{n}\right),$$ here is the unknown function $u_n (x)$ depends on one discrete $n$ and one continuous $x$ variables. The classification is based on the requirement for the existence of higher symmetries in the discrete and continuous directions. The case is considered when the symmetries are of order 3 in both directions. As a result, a list of equations with the required conditions is obtained.

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R. N. Garifullin. 2022-12-05. Classification of semidiscrete hyperbolic type equations. The case of third order symmetries. https://doi.org/10.4213/tmf10512

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