Some classes of numbers and derivatives.
Some combinatorial problems, connected with product-isomorphisms of binary relations
Some combinatorial results about the operators with jumping nonlinearities
Some computational formulas for -Nörlund numbers.
Some easily derivable integer sequences.
Some equinumerous pattern-avoiding classes of permutations.
Some formulas for the central trinomial and Motzkin numbers.
Some formulas that enumerate certain partitions and graphs
Some further results on Legendre numbers.
Some generalized Fibonacci polynomials.
Some generating functions for polynomials
Some geometric probability problems involving the Eulerian numbers.
Some identities for Chebyshev polynomials.
Some observations on the Lah and Laguerre transforms of integer sequences.
Some Parity Statistics in Integer Partitions
We study integer partitions with respect to the classical word statistics of levels and descents subject to prescribed parity conditions. For instance, a partition with summands may be enumerated according to descents while tracking the individual parities of and . There are two types of parity levels, E = E and O = O, and four types of parity-descents, E > E, E > O, O > E and O > O, where E and O represent arbitrary even and odd summands. We obtain functional equations and explicit...
Some properties of associated Stirling numbers.
Some -analogues of determinant identities which arose in plane partition enumeration.
Some remarks on the enumeration of rooted trees
Sorting classes.
Sorting with a forklift.