The permanent-non-singular (1,1)(1,1)-matrix conjecture

Let GG be a graph, and orient its edges arbitrarily. Define the graph matrix AGA_G with rows indexed by E(G)E(G) and columns indexed by V(G)E(G)V(G)\cup E(G) by assigning to an oriented edge e=(u,v)e=(u,v) the entries 11 in the column for vv and for edges other than ee incident with vv, 1-1 in the column for uu and for edges other than ee incident with uu, and 00 elsewhere. For an index function η\eta, let AG(η)A_G(\eta) repeat the column indexed by zz exactly η(z)\eta(z) times. An (a,b)(a,b)-matrix is a square matrix AG(η)A_G(\eta) with η(v)a\eta(v)\le a for every vertex and η(e)b\eta(e)\le b for every edge; it is permanent-non-singular when its permanent is nonzero. The permanent-non-singular (1,1)(1,1)-matrix conjecture. Every graph GG has a permanent-non-singular (1,1)(1,1)-matrix. This matrix formulation is motivated by total-weighting and edge-weighting problems; the stated status evidence says the conjecture is resolved for wheels and Halin graphs, while no general resolution is supplied here.

Sources & referencesView supporting material

Primary source

Yu-Chang Liang, Tsai-Lien Wong and Xuding Zhu, “Total weight choosability for Halin graphs”, arXiv:1705.08150 (2017).

Progress summary

Never refreshed

Nothing recorded yet. Refresh searches the literature and the public web for attempts on this problem, and writes the first summary here.

Solutions 0

No solutions have been posted yet.