3 papers
math.AT2017
On surface-knots with triple point number at most three
Amal Al Kharusi, Tsukasa Yashiro
In this paper, we show that if a diagram of a surface-knot has at most three triple points, then the cocyle invariant of is an integer. In particular, for a surface-knot of…
math.AT2015
On Crossing Changes for Surface-Knots
A. Al Kharusi, T. Yashiro
In this paper, we discuss the crossing change operation along exchangeable double curves of a surface-knot diagram. We show that under certain condition, a finite sequence of Rosem…
math.AT2015
No surface-knot of genus one has triple point number two
A. Al Kharusi, T. Yashiro
It is known that there is no 2-knot with triple point number two. The present work shows that there is no surface-knot of genus one with triple point number two. In order to prove…