Word Equations Where a Power Equals a Product of Powers
نویسنده
چکیده
We solve a long-standing open problem on word equations by proving that if the words x0, . . . , xn satisfy the equation x0 = x1 · · ·xn for three positive values of k, then the words commute. One of our methods is to assign numerical values for the letters, and then study the sums of the letters of words and their prefixes. We also give a geometric interpretation of our methods. 1998 ACM Subject Classification G.2.1 Combinatorics, F.4.3 Formal Languages
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تاریخ انتشار 2017