English

Maps on Surfaces as a Structural Framework for Genus-One Virtual Knot Classification

Combinatorics 2026-01-23 v1 Geometric Topology

Abstract

We develop a purely combinatorial framework for the systematic enumeration of knot and link diagrams supported on the thickened torus T2×IT^2\times I. Using the theory of maps on surfaces, cellular 44--regular torus projections are encoded by permutation pairs (α,σ)(\alpha,\sigma), and unsensed projection classes are enumerated completely and without duplication via canonical representatives. For a fixed projection, crossing assignments are encoded by bit data, and an immediate Reidemeister~II reduction supported by a bigon face is characterized directly in terms of these bits. The genus-one generalized Kauffman-type bracket is then evaluated as a state sum entirely within the permutation model, without drawing diagrams in a fundamental polygon. The implementation is validated against published genus-one classifications for N5N\le 5 under explicit comparison conventions, with remaining discrepancies explained at the level of global conventions. Beyond the published range, we compute projection and diagram data for crossing numbers up to N=8N=8 and provide a public reference implementation together with machine-readable datasets. Via the standard correspondence between virtual knots and knots in thickened surfaces, this yields a canonical and fully reproducible genus-one framework for virtual knot tabulation.

Keywords

Cite

@article{arxiv.2601.15512,
  title  = {Maps on Surfaces as a Structural Framework for Genus-One Virtual Knot Classification},
  author = {Alexander Omelchenko},
  journal= {arXiv preprint arXiv:2601.15512},
  year   = {2026}
}

Comments

26 pages, 3 tables. Algorithm for N up to 8 is described

R2 v1 2026-07-01T09:14:59.830Z