128,844 research outputs found
An algorithm for primary decomposition in polynomial rings over the integers
We present an algorithm to compute a primary decomposition of an ideal in a
polynomial ring over the integers. For this purpose we use algorithms for
primary decomposition in polynomial rings over the rationals resp. over finite
fields, and the idea of Shimoyama-Yokoyama resp. Eisenbud-Hunecke-Vasconcelos
to extract primary ideals from pseudo-primary ideals. A parallelized version of
the algorithm is implemented in SINGULAR. Examples and timings are given at the
end of the article.Comment: 8 page
On the Enumeration of all Minimal Triangulations
We present an algorithm that enumerates all the minimal triangulations of a
graph in incremental polynomial time. Consequently, we get an algorithm for
enumerating all the proper tree decompositions, in incremental polynomial time,
where "proper" means that the tree decomposition cannot be improved by removing
or splitting a bag
- …