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arXiv · 1112.4256

A Sufficient Condition for Hanna Neumann Property of Submonoids of a Free Monoid

Shubh Narayan Singh·K. V. Krishna
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Abstract

Using automata-theoretic approach, Giambruno and Restivo have investigated on the intersection of two finitely generated submonoids of the free monoid over a finite alphabet. In particular, they have obtained Hanna Neumann property for a special class of submonoids generated by finite prefix sets. This work continues their work and provides a sufficient condition for Hanna Neumann property for the entire class of submonoids generated by finite prefix sets. In this connection, a general rank formula for the submonoids which are accepted by semi-flower automata is also obtained.

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Shubh Narayan Singh, K. V. Krishna. 2011-12-19. A Sufficient Condition for Hanna Neumann Property of Submonoids of a Free Monoid. https://doi.org/10.1007/s00233-012-9449-4

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