Multiple almost-Riordan arrays and the multiple almost-Riordan group

Building upon the study of multiple Riordan arrays and the multiple Riordan group, this paper introduces the concept of multiple almost-Riordan arrays and demonstrates that the collection of all such arrays forms a group, referred to as the multiple almost-Riordan group. The sequence characteristics and some properties of multiple almost-Riordan arrays are derived, and their corresponding production matrices are presented. Furthermore, the compression of multiple almost-Riordan arrays is defined, together with their sequence characterizations.