id summary reporter owner description type status priority milestone component resolution keywords cc merged author reviewer upstream work_issues branch commit dependencies stopgaps
14562 Steiner Quadruple Systems ncohen sage-combinat "Wow.
This patch is scary.
Really scary.
The construction is awful, and there's not much that I could do to make the code clear.
The point is that I do not understand the construction myself, and I did not try either, I just wanted to implement it. And it already took Quiiiiiiiiiiiiiite a lot of time, and headaches `:-)`
This patch implements a method that returns a Steiner Quadruple System whenever it exists. It follows the construction from Haim Hanani in a paper from 1960, which gives 6 differents constructions to make a large system from a small one, and all must be used to solve all cases.
Considering that I was able to test this code until `n =300`, and that all constructions have been tested for different values of `n`, I believe that this code is a correct counterpart of the paper itself. That's what makes me think that there is no typo in the code anymore (I fixed one thousand of them while writing it). So, even if it is very, very scary and unclear, I think that it is correct... Experimentally `:-)`
Nathann" enhancement closed major sage-5.10 combinatorics fixed azi sage-5.10.beta3 Nathann Cohen Volker Braun N/A