An explicit description of the second cohomology group of a quandle
arXiv:1512.01262 · doi:10.1007/s00209-016-1794-7
Abstract
We use the inflation-restriction sequence and a result of Etingof and Graña on the rack cohomology to give a explicit description of 2-cocycles of finite indecomposable quandles with values in an abelian group. Several applications are given.
22 pages. Accepted for publication in Mathematische Zeitschrift