Lower estimate of Tandori’s norm
Tóm tắt
The conventional monotonicity hypothesis on the coefficients given in the sharpest lower estimate of the celebrated Tandori-norm is weakened to locally almost monotonicity assumption.
Tài liệu tham khảo
G. Alexits, Convergence problems of orthogonal series, Pergamon (New York-Oxford-London-Paris, 1961).
D. E. Menchoff, Sur les séries de fonctions orthogonales, Fundamenta Math., 4(1923), 82–105.
K. Tandori, Über die Konvergenz der Orthogonalreihen. II, Acta Sci. Math. (Szeged), 25(1964), 219–232.