On coideal subalgebras of cocentral Kac algebras and a generalization of   Wall's conjecture
  It shown that any coideal subalgebra of a finite dimensional Hopf algebra is a cyclic module over the dual Hopf algebra. Using this we describe all coideal subalgebras of a cocentral abelian extension of Hopf algebras extending some results from [4]. 
Sebastian Burciu
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