Symbolic Summation and the Interlacing Method in Difference Rings

There exist strong tools to solve recurrences in terms of indefinite nested sums defined over hypergeometric products (so-called d'Alembertian solutions). Besides sum and product quantifiers one may also incorporate the interlacing operator of sequences which leads to the so-called Liouvillian solutions of linear recurrences. In this master thesis the available techniques are explored, impemented and applied to concrete problem solving.