Addendum: "(1, 2) and weak (1, 3) homotopies on knot projections"

Noboru Ito, Yusuke Takimura*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


After this paper was published, the following information about doodles was pointed out by Roger Fenn. A doodle was introduced by Fenn and Taylor [2], which is a finite collection of closed curves without triple intersections on a closed oriented surface considered up to the second flat Reidemeister moves with the condition (*) that each component has no self-intersections. Khovanov [4] introduced doodle groups, and for his process, he considered doodles under a more generalized setting (i.e. removing the condition (*) and permitting the first flat Reidemeister moves). He showed [4, Theorem 2.2], a result similar to our [3, Theorem 2.2(c)]. He also pointed out that [1, Corollary 2.8.9] gives a result similar to [4, Theorem 2.2].

The authors first noticed the above results by Fenn and Khovanov via personal communication with Fenn, and therefore, the authors would like to thank Roger Fenn for these references.

Original languageEnglish
JournalJournal of Knot Theory and its Ramifications
Publication statusAccepted/In press - 2014 Sept 9
Externally publishedYes


  • (1, 2) homotopy
  • flat Reidemeister move
  • Knot projection
  • weak (1, 3) homotopy

ASJC Scopus subject areas

  • Algebra and Number Theory


Dive into the research topics of 'Addendum: "(1, 2) and weak (1, 3) homotopies on knot projections"'. Together they form a unique fingerprint.

Cite this