Abstract
For a ring endomorphism α, we introduce and investigate SPA-rings which are a generalization of α-rigid rings and determine the radicals of the skew polynomial rings R[x; α], R[x, x −1; α] and the skew power series rings R[[x; α]], R[[x, x −1; α]], in terms of those of R. We prove that several properties transfer between R and the extensions, in case R is an SPA-ring. We will construct various types of nonreduced SPA-rings and show SPA is a strictly stronger condition than α-rigid.
ACKNOWLEDGMENT
The authors are thankful to the referee for a careful reading of the article and for some helpful comments and suggestions.
Notes
Communicated by V. A. Artamonov.