Harper’s operator is defined on by where . We show that the norm of is less than or equal to for . This solves a conjecture stated in [1]. A general formula for estimating the norm of self-adjoint tridiagonal infinite matrices is also derived.
@article{bwmeta1.element.bwnjournal-article-cmv76z1p153bwm, author = {Ryszard Szwarc}, title = {Norm estimates of discrete Schr\"odinger operators}, journal = {Colloquium Mathematicae}, volume = {78}, year = {1998}, pages = {153-160}, zbl = {0904.47025}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-cmv76z1p153bwm} }
Szwarc, Ryszard. Norm estimates of discrete Schrödinger operators. Colloquium Mathematicae, Tome 78 (1998) pp. 153-160. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-cmv76z1p153bwm/
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