Congruence preserving functions on free monoids
نویسندگان
چکیده
منابع مشابه
Congruence Preserving Functions on Free Monoids
A function on an algebra is congruence preserving if, for any congruence, it maps congruent elements to congruent elements. We show that, on a free monoid generated by at least three letters, a function from the free monoid into itself is congruence preserving if and only if it is of the form x 7→ w0xw1 · · ·wn−1xwn for some finite sequence of words w0, . . . , wn. We generalize this result to ...
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ژورنال
عنوان ژورنال: Algebra universalis
سال: 2017
ISSN: 0002-5240,1420-8911
DOI: 10.1007/s00012-017-0464-x