Enumerative problems in some matrix rings and finite groups

In this article were obtained several new results for the combinatorial numbers which arised earlier in an implicit kind by an enumeration of ideals of nilpotent ring of matrices over finite ring (G.P. Egorychev, V.M. Levchuk, 2001) and also the numbers of pairs of generating projective special linear groups of dimension 2 and the Suzuki groups over finite fields of the characteristic 2 (N. M. Suchkov and D. P. Prihodko, 2001). These results were obtained by authors with the help of the Egorychev's method of integral representation and computing of combinatorial sums (the set of inference rules and the Completeness Lemma) developed by him to the end 1970.
Some new problems are put and planned prospect of the further researches.