Rank 4 Nichols Algebras of Pale Braidings

Nicolás Andruskiewitsch, Iván Angiono, Matías Moya Giusti

We classify finite GK-dimensional Nichols algebras $\mathcal{B}(V)$ of rank 4 such that $V$ arises as a Yetter-Drinfeld module over an abelian group but it is not a direct sum of…