Principal Functions of Nonselfadjoint Discrete Dirac Equations with Spectral Parameter in Boundary Conditions.

Let L denote the operator generated in ℓ2(N, C2) by an+1yn+1 (2) + bnyn(2) + pnyn(1) = λyn(1), an-1 yn-1(1)+bnyn (1)+qnyn(2) = λyn(2), n∈N and the boundary condition (γ0 + γ1λ)y1(2) + ( β0 + β1λ)y0(1) = 0, where (an), (bn),(pn), and (qn), n ∈ N are complex sequences γi, βi ∈ C, i =0,1, and λ is an eigenparameter. In this paper we investigated the principal functions corresponding to the eigenvalues and the spectral singularities of L. [ABSTRACT FROM AUTHOR]