PUBLICATIONS DE L'INSTITUT MATHÉMATIQUE (BEOGRAD) (N.S.) Vol. 39(53), pp. 129133 (1986) 

ON THE CONVERGENCE OF BIORTHOGONAL SERIES CORRESPONDING TO NONSELFADJOINT STURMLIOUVILLE OPERATOR WITH DISCONTINUOUS COEFFICIENTSNebojsa L\. Lazeti\'cMatematicki fakultet, Beograd, YugoslaviaAbstract: We consider the convergence of the biorthogcnal series corresponding to the nonselfadjoint SturmLiouville operator at the points of discontinuity of its coefficients. For any function $f(x)\in L_2$ we construct a function $\tilde f_{x_0}(x)$ such that the trigonometrical Fourier series of $\tilde f_{x_0}(x)$ is convergent at the point of discontinuity $x_0$ if and only if the biorthogonal series of $f(x)$ is convergent at this point. Classification (MSC2000): 34B25 Full text of the article:
Electronic fulltext finalized on: 2 Nov 2001. This page was last modified: 16 Nov 2001.
© 2001 Mathematical Institute of the Serbian Academy of Science and Arts
