Abstract:
We construct an example of an asymmetric dictionary D in a Hilbert space H such that the linear combinations of elements of D with positive coefficients are dense in H, but the greedy algorithm with respect to D, in which inner product with the elements of D (not the modulus of this inner product) is maximized at each step, diverges for some initial element.
Citation:
P. A. Borodin, “Example of Divergence of a Greedy Algorithm with Respect to an Asymmetric Dictionary”, Mat. Zametki, 109:3 (2021), 352–360; Math. Notes, 109:3 (2021), 379–385