Doron Zeilberger, Manuel Kauers,
"Experiments with a Positivity Preserving Operator"
, Serie SFB F013, Nummer 2007-21, SFB F013, Johannes Kepler University Linz, Altenbergerstraße 69, 4040 Linz, Austria, 2007
Experiments with a Positivity Preserving Operator
Sprache des Titels:
We consider some multivariate rational functions which have (or are conjectured to have) only positive coefficients in their series expansion. We consider an operator that preserves positivity of series coefficients, and apply the inverse of this operator to the rational functions. We obtain new rational functions which seem to have only positive coefficients, whose positivity would imply positivity of the original series, and which, in a certain sense, cannot be improved any further.
Sprache der Kurzfassung:
Johannes Kepler University Linz, Altenbergerstraße 69, 4040 Linz, Austria