Spanning trees in directed square cycles
We classify weakly connected spanning closed (WCSC) subgraphs of C n 2 ⃗ , the square of a directed n -vertex cycle. Then we show that every spanning tree of C n 2 ⃗ is contained in a unique nontrivial WCSC subgraph of C n 2 ⃗ . As a result, we obtain a purely combinatorial derivation of the formula for the number of directed spanning trees of C n 2 ⃗ . Moreover, we obtain the formula for the number of directed spanning trees of C n 2 ⃗ , which is a Jacobsthal number.
Authors
- Yuuho Tanaka
Institutions
- Oita University (JP)
Publication Details
- Journal
- Discrete Applied Mathematics
- Published
- 2025-10-09
- DOI
- https://doi.org/10.1016/j.dam.2025.10.005
- Primary Topic
- Advanced Graph Theory Research
- Type
- article
- Field-Weighted Citation Impact
- 0.00