3 papers
math.CO2026
Partial-twuality polynomial interpolation for binary delta-matroids
Zhuo Li, Qi Yan, Xian'an Jin
Gross, Mansour and Tucker introduced the partial-twuality polynomials for ribbon graphs and investigated the interpolation property of these polynomials. The ribbon group generated…
math.CO2026
On the maximum twist width of delta-matroids
Xian'an Jin, Zhuo Li, Qi Yan +1
For a ribbon graph , let denote its Euler genus. Recently, Chen, Gross and Tucker [J. Algebraic Combin. 63 (2026) 13] derived a formula for the maximum partial-dual Eule…
math.CO2025
Orbits and self-twuality in set systems and delta-matroids
Zhuo Li, Xian'an Jin, Qi Yan
We introduce a new group action on set systems, constructed as a semidirect product of a permutation group and a group generated by twist and loop complementation operations on a s…