Normal cyclotomic schemes over a finite commutative ring
نویسندگان
چکیده
We study cyclotomic association schemes over a finite commutative ring R with identity. The main interest for us is to identify the normal cyclotomic schemes C, i.e. those for which Aut(C) ≤ AΓL1(R). The problem is reduced to the case when the ring R is local in which a necessary condition of normality in terms of the subgroup of R defining C, is given. This condition is proved to be sufficient for a class of local rings including the Galois rings of odd characteristic.
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