On a class of inhomogeneous extensions for integrable evolution systems

A. Sergyeyev

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arXiv · nlin/0310032

On a class of inhomogeneous extensions for integrable evolution systems

A. Sergyeyev

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Abstract

In the present paper we prove the integrability (in the sense of existence of formal symmetry of infinite rank) for a class of block-triangular inhomogeneous extensions of (1+1)-dimensional integrable evolution systems. An important consequence of this result is the existence of formal symmetry of infinite rank for "almost integrable" systems, recently discovered by Sanders and van der Kamp.

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A. Sergyeyev. 2003-10-21. On a class of inhomogeneous extensions for integrable evolution systems. https://arxiv.org/abs/nlin/0310032

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