A notion of minor-based matroid connectivity
A notion of minor-based matroid connectivity
复制标题
基于次要拟阵连接的概念
DOI:
10.1016/j.aam.2018.07.001
复制
发表时间:
2017
影响因子:
1.1
通讯作者:
James G. Oxley
中科院分区:
文献类型:
--
作者:
Zachary Gershkoff;James G. Oxley
For a matroid N, a matroid M is N-connected if every two elements of M are in an N-minor together. Thus a matroid is connected if and only if it is U 1, 2-connected. This paper proves that U 1, 2 is the only connected matroid N such that if M is N-connected with| E (M)|>| E (N)|, then M\e or M/e is N-connected for all elements e. Moreover, we show that U 1, 2 and M (W 2) are the only matroids N such that, whenever a matroid has an N-minor using {e, f} and an N-minor using {f, g}, it also has an N-minor using {e, g}. Finally, we show that M is U 0, 1⊕ U 1, 1-connected if and only if every clonal class of M is trivial.