ON THE SPECTRUM AND FINE SPECTRUM OF THE UPPER TRIANGULAR DOUBLE BAND MATRIX U (a0, a1, a2; b0, b1, b2) OVER THE SEQUENCE SPACE lp

The purpose of this article is to obtain the spectrum, fine spectrum, approximate point spectrum, defect spectrum and compression spectrum of the double band matrix U (a(0), a(1), a(2); b(0), b(1), b(2)), b(0), b(1), b(2) not equal 0 on the sequence space l(p) (1 < p < infinity).