2 papers
math.CV2005
Multiple positivity and the Riemann zeta-function
Olga M. Katkova
In the paper it is discussed the relations of the Riemann function to classes of generating functions of multiply positive sequences according to Schoenberg (also called Pólya…
math.RA2005
On sufficient conditions for the total positivity and for the multiple positivity of matrices
Olga M. Katkova, Anna M. Vishnyakova
The following theorem is proved: Suppose be a matrix with positive entries and $a_{i,j}a_{i+1,j+1} > 4\cos ^2 \fracπ{k+1} a_{i,j+1}a_{i+1,j} \quad (1 \…