Given a smooth proper dg algebra , a perfect dg -module and an endomorphism of , we define the Hochschild class of the pair with values in the Hochschild homology of the algebra . Our main result is a Riemann-Roch type formula involving the convolution of two such Hochschild classes.
We show that there are exactly three types of Hilbert series of Artin-Schelter regular algebras of dimension five with two generators. One of these cases (the most extreme) may not be realized by an enveloping algebra of a graded Lie algebra. This is a new phenomenon compared to lower dimensions, where all resolution types may be realized by such enveloping algebras.