Hochschild cohomology of the quadratic monomial algebra ${\mathrm{N}}_m$

Tomohiro Itagaki, Kazunori Nakamoto, Takeshi Torii

Let ${\rm N}_m(R) = \{ (a_{ij}) \in {\rm M}_m(R) \mid a_{11} = a_{22} = \cdots = a_{mm} \mbox{ and } a_{ij} = 0 \mbox{ for any } i > j \}$ for a commutative ring $R$. Then ${\rm N}…