A Recursive Presentation for Mihailova’s Subgroup
نویسنده
چکیده
We give an explicit recursive presentation for Mihailova’s subgroup M(H) of Fn×Fn corresponding to a finite, concise and Peiffer aspherical presentation H = 〈x1, . . . , xn |R1, . . . , Rm〉. This partially answers a question of R.I. Grigorchuk, [8, Problem 4.14]. As a corollary, we construct a finitely generated recursively presented orbit undecidable subgroup of Aut(F3).
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تاریخ انتشار 2008