Expressing Infinite Matrices as Sums of Idempotents

On the idempotent and nilpotent sum numbers of matrices over certain indecomposable rings and related concepts

“…Moreover, in [29] were established some matrix presentations over the indecomposable ring Z 4 and some other commutative rings (resp., fields) into the sum of three idempotents or three involutions. Likewise, in [25,26] were considered those (infinite) matrices which are expressed as sums of three or more idempotents (see [27] too).…”