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.
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Acknowledgements
We thank G. García and M. Kotchetov for interesting discussions. We also thank N. Andruskiewitsch for his constant guidance and support. This work was initiated while the authors were visiting María Ofelia Ronco, at Universidad de Talca, Chile. We are grateful for her warm hospitality. The authors are grateful to the reviewer for useful remarks, interesting suggestions and corrections.
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This work is partially supported by CONICET, FONCyT PICT-2013-1414 and PICT-2014-1376, Secyt (UNC), ICTP and MATH-AmSud.
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García Iglesias, A., Vendramin, L. An explicit description of the second cohomology group of a quandle. Math. Z. 286, 1041–1063 (2017). https://doi.org/10.1007/s00209-016-1794-7
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DOI: https://doi.org/10.1007/s00209-016-1794-7