Document Type : Research Paper


School of Mathematics and Computer Science, Damghan University, Department of Mathematics, Damghan University,P.O. Box 36715-364, Damghan, Iran.


In this paper, a new  algorithm for computing secondary invariants of  invariant rings of monomial groups is presented. The main idea is to compute simultaneously a truncated SAGBI-\G basis and the standard invariants of the ideal generated by the set of primary invariants.  The advantage of the presented algorithm lies in the fact that it is well-suited to complexity analysis and very easy to implement.