A solution to Ringel's circle problem
The spectrum and toughness of regular graphs
Symmetry-free SDP Relaxations for Affine Subspace Clustering A titanium-nitride near-infrared kinetic inductance photon-counting
  detector and its anomalous electrodynamics Wall-Crossing functors and D-modules Generalized minimum distance functions and algebraic invariants of
  Geramita ideals Linear and nonlinear information flow in spatially extended systems Weak line discovered by Voyager 1 in the interstellar medium:
  Quasi-thermal noise produced by very few fast electrons Calculating Nash Equilibrium on Quantum Annealers The breakdown of the reaction-diffusion master equation with
  non-elementary rates How to refine polynomial functions Paradoxes of magnetorotational instability and their geometrical
  resolution Environmental Policy Regulation and Corporate Compliance in a Spatial
  Evolutionary Game Model Shafranov's virial theorem and magnetic plasma confinement Gr\"obner Bases over Algebraic Number Fields Data assimilation and online optimization with performance guarantees Parameter Synthesis for Cardiac Cell Hybrid Models Using Delta-Decisions Mechanism of magnetism in stacked nanographite with open shell electrons Revealing surface states in In-doped SnTe superconducting nanoplates
  with low bulk mobility SENNS: Sparse Extraction Neural NetworkS for Feature Extraction
math.CO cs.DM