The Number of Indecomposable Schur Rings over a Cyclic 2-group
نویسنده
چکیده
Indecomposable Schur rings over a cyclic group Zn of order n are considered. In the case n = p, p an odd prime, the total number of such rings was described in terms of Catalan numbers by Liskovets and Pöschel [Discr. Math. 214 (2000), 173–191]. Here, a closed formula is shown for the total number of indecomposable Schur rings over Z2m using Catalan and Schröder numbers. The result is obtained after the initial problem is turned into a lattice path problem.
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تاریخ انتشار 2005