1. CJM 2006 (vol 58 pp. 249)
2. CJM 2005 (vol 57 pp. 941)
 Berg, Christian; Durán, Antonio J.

Some Transformations of Hausdorff Moment Sequences and Harmonic Numbers
We introduce some nonlinear transformations from the set of
Hausdorff moment sequences into itself; among
them is the one defined by
the formula:
$T((a_n)_n)=1/(a_0+\dots +a_n)$. We give some examples of
Hausdorff moment sequences arising from the transformations and
provide the corresponding measures: one of these sequences is the
reciprocal of the harmonic numbers $(1+1/2+\dots +1/(n+1))^{1}$.
Categories:44A60, 40B05 

3. CJM 1997 (vol 49 pp. 708)
 Duran, Antonio J.; LopezRodriguez, Pedro

Density questions for the truncated matrix moment problem
For a truncated matrix moment problem, we describe in detail
the set of positive definite matrices of measures $\mu$ in $V_{2n}$ (this is
the set of solutions of the problem of degree $2n$) for which the polynomials
up to degree $n$ are dense in the corresponding space ${\cal L}^2(\mu)$.
These matrices of measures are exactly the extremal measures of the set $V_n$.
Categories:42C05, 44A60 
