Chen, Kan; Li, Jinqi On \(\pi\)-twisted smash coproducts and \(\pi\)-\(L\)-\(R\) smash coproducts. (Chinese. English summary) Zbl 1212.16068 J. Zhejiang Norm. Univ., Nat. Sci. 32, No. 4, 385-391 (2009). Summary: The notions of \(\pi\)-smash coproducts, \(\pi\)-twisted smash coproducts and \(\pi\)-\(L\)-\(R\) smash coproducts are introduced. It is proved that they are all \(\pi\)-coalgebras, and a necessary condition for \(\pi\)-smash coproducts to be Hopf \(\pi\)-coalgebras is given. For any finite type Hopf \(\pi\)-coalgebras, it is proved that there exists a \(\pi\)-coalgebra isomorphism between \(\pi\)-twisted smash coproducts and \(\pi\)-\(L\)-\(R\) smash coproducts if each \(H_\alpha\) is commutative. MSC: 16T15 Coalgebras and comodules; corings 16S40 Smash products of general Hopf actions Keywords:twisted smash coproducts; Hopf coalgebras PDFBibTeX XMLCite \textit{K. Chen} and \textit{J. Li}, J. Zhejiang Norm. Univ., Nat. Sci. 32, No. 4, 385--391 (2009; Zbl 1212.16068)