Nearly Gorenstein cyclic quotient singularities

Abstract

We investigate the nearly Gorenstein property among d-dimensional cyclic quotient singularities $$\Bbbk \llbracket x_1,\dots ,x_d\rrbracket ^G$$ k 〚 x 1 , ⋯ , x d 〛 G , where $$\Bbbk $$ k is an algebraically closed field and $$G\subseteq {\text {GL}}(d,\Bbbk )$$ G ⊆ GL ( d , k ) is a finite small cyclic group whose order is invertible in $$\Bbbk $$ k . We prove a necessary and sufficient condition to be nearly Gorenstein that also allows us to find several new classes of such rings.