From any element a of a ring R with unity, we set τ(a) = {e ∈ R|e3 = e and a - e E Nil(R)}, where Nil(R) is the set of all nilpotent elements of R; trinil clean index of R is defined by sup {|τ(a)||aR} and it is denoted by Trinin(R). Motivated by the trinil clean index of any ring Zn for any positive integer n ≥ 2, we expand these results by determined the trinil clean index of upper triangular matrix 2 × 2 over Zn which n is positive integer greater than 2.

1.
W. K.
Nicholson
, “
Lifting idempotents and exchange rings
,” in
Trans. Amer. Math. Soc.,
pp.
269
278
(
1977
).
2.
T. K.
Lee
and
Y.
Zhou
, “
Clean index of rings
” in
Comm. Algebra
, pp.
807
822
(
2012
).
3.
A. J.
Diesl
, “
Nil clean rings
” in
Journal Algebra
, pp.
197
211
(
2013
).
4.
D. K.
Basnet
and
J.
Bhattacharyya
, “
Nil clean index of rings
” in
International Electron. Journal Algebra
, pp.
45
156
(
2014
).
5.
P. V.
Danchev
and
W. W.
McGovern
, “
Commutative weakly nil clean unital rings
” in
Journal Algebra
, pp.
410
422
(
2015
).
6.
A.
Cimpean
and
P. V.
Danchev
, “
Weakly nil clean index and uniquely weakly nil clean rings
,” in
International Electron. Journal Algebra
, pp.
180
197
(
2017
).
7.
H.
Chen
and
M.
Sheibani
, “
Rings over which every matrix is the sum of a tripotent and a nilpotent
,” in
Bull. Korean Math. Soc.
, pp.
1
8
(
2017
).
8.
G.
Calugareanu
, “
Tripotens: a class of strongly clean elements in rings
,” in
Versita
26
(
1
) pp.
69
80
(
2018
).
9.
A. Mu
in
,
S.
Irawati
,
H.
Susanto
,
M.
Agung
, and
H.
Marubayashi
, “
Trinil Clean Index of a Ring
”, in
Journal of Physics: Conference Series
, (
2021
).
10.
W. A.
Adkins
and
S. H.
Weintraub
,
Algebra an approach via module theory
(
Springer
,
Verlag-New York
,
1992
).
This content is only available via PDF.
You do not currently have access to this content.