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Third-order integrable difference equations generated by a pair of second-order equations

Junta Matsukidaira·Daisuke Takahashi
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Abstract

We show that the third-order difference equations proposed by Hirota, Kimura and Yahagi are generated by a pair of second-order difference equations. In some cases, the pair of the second-order equations are equivalent to the Quispel-Robert-Thomson(QRT) system, but in the other cases, they are irrelevant to the QRT system. We also discuss an ultradiscretization of the equations.

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Junta Matsukidaira, Daisuke Takahashi. 2005-12-26. Third-order integrable difference equations generated by a pair of second-order equations. https://doi.org/10.1088/0305-4470%2F39%2F5%2F009

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