3.21 q-Laguerre

Definition.

 

Orthogonality. The q-Laguerre polynomials satisfy two kinds of orthogonality relations, an absolutely continuous one and a discrete one. These orthogonality relations are given by, respectively :

 

and

 

Recurrence relation.

 

Normalized recurrence relation.

 

where

q-Difference equation.

 

where

Forward shift operator.

 

or equivalently

 

Backward shift operator.

 

or equivalently

 

where

Rodrigues-type formula.

 

Generating functions.

 

 

 

 

Remarks. The q-Laguerre polynomials are sometimes called the generalized Stieltjes-Wigert polynomials.

If we change q to we obtain the little q-Laguerre (or Wall) polynomials given by (3.20.1) in the following way :

The q-Laguerre polynomials defined by (3.21.1) and the alternative q-Charlier polynomials given by (3.22.1) are related in the following way :

The q-Laguerre polynomials defined by (3.21.1) and the q-Charlier polynomials given by (3.23.1) are related in the following way :

Since the Stieltjes and Hamburger moment problems corresponding to the q-Laguerre polynomials are indeterminate there exist many different weight functions.

References. [11], [13], [42], [43], [64], [71], [116], [121], [123], [124], [156], [193], [203], [235], [246], [319].




Last modified on July 6, 1998