U. Shankar

activity

20202023

collaborators

3 papers

math.CO2023

Enumeration of flattened $k$ -Stirling permutations with respect to descents

Umesh Shankar

A $k$ -Stirling permutation of order $n$ is said to be "flattened" if the leading terms of its increasing runs are in ascending order. We show that flattened $k$ -Stirling permutatio…

math.CO2022

$q$ -enumeration of type B and D Eulerian polynomials based on parity of descents

Hiranya Kishore Dey, Umesh Shankar, Sivaramakrishnan Sivasubramanian

Carlitz and Scoville in 1973 considered a four variable polynomial that enumerates permutations in $S_{n}$ with respect to the parity of its descents and ascents. In recen…

math.NT2020

On zero-sum subsequences of length exp(G)

Srilakshmi Krishnamoorthy, Karthikesh, Umesh Shankar

Let $G$ be a finite abelian group. Let $g (G)$ be the smallest positive integer $t$ such that every subset of cardinality $t$ of the group $G$ contains a subset of cardinality $\mat…

Enumeration of flattened k-Stirling permutations with respect to descents

q-enumeration of type B and D Eulerian polynomials based on parity of descents

On zero-sum subsequences of length exp(G)

Enumeration of flattened $k$ -Stirling permutations with respect to descents

$q$ -enumeration of type B and D Eulerian polynomials based on parity of descents