@article{Durna_2018, title={Subdivision of spectra for some lower triangular double-band matrices as operators
on $c_0$}, volume={70}, url={http://umj.imath.kiev.ua/index.php/umj/article/view/1605}, abstractNote={The generalized difference operator $\Delta_{a,b}$ was defined by El-Shabrawy: $\Delta{a,b}x = \Delta_{a,b} (x_n) = (a_nx_n + b_{n-1}x_{n-1})^{\infty}_{n = 0}$
with $x_1 = b_1 = 0$, where $(a_k), (b_k)$ are convergent sequences of nonzero real numbers satisfying certain conditions.
We completely determine the approximate point spectrum, the defect spectrum, and the compression spectrum of the operator
$\Delta_{a,b}$ in the sequence space $c_0$.}, number={7}, journal={Ukrainsâ€™kyi Matematychnyi Zhurnal}, author={Durna, N.}, year={2018}, month={Jul.}, pages={913-922} }