Conditions for the existence of higher symmetries of evolutionary equations on the lattice

  title={Conditions for the existence of higher symmetries of evolutionary equations on the lattice},
  author={Decio Levi and Ravil I. Yamilov},
  journal={Journal of Mathematical Physics},
  • D. Levi, R. Yamilov
  • Published 1 December 1997
  • Mathematics
  • Journal of Mathematical Physics
In this paper we construct a set of five conditions necessary for the existence of generalized symmetries for a class of differential-difference equations depending only on nearest neighboring interaction. These conditions are applied to prove the existence of new integrable equations belonging to this class. 
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    Proceedings of the National Academy of Sciences of the United States of America
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