17 citations · 52 across the 11 of their papers we have counts for
11 papers
A Symbolic Treatment of Riordan Arrays
José Agapito, Ângela Mestre, Pasquale Petrullo +1
We approach Riordan arrays and their generalizations via umbral symbolic methods. This new approach allows us to derive fundamental aspects of the theory of Riordan arrays as immed…
On One-Parameter Catalan Arrays
José Agapito, Ângela Mestre, Pasquale Petrullo +1
We present a parametric family of Riordan arrays which are obtained by multiplying any Riordan array with a generalized Pascal array. In particular, we focus on some interesting pr…
Several graph sequences as solutions of a double recurrence
Christian Brouder, William J. Keith, Ângela Mestre
We describe the combinatorics that arise in summing a double recursion formula for the enumeration of connected Feynman graphs in quantum field theory. In one index the problem is…
Riordan arrays and applications via the classical umbral calculus
José Agapito, Ângela Mestre, Pasquale Petrullo +1
We use the classical umbral calculus to describe Riordan arrays. Here, a Riordan array is generated by a pair of umbrae, and this provides efficient proofs of several basic results…
Combinatorics of 1-particle irreducible n-point functions via coalgebra in quantum field theory
Angela Mestre
We give a coalgebra structure on 1-vertex irreducible graphs which is that of a cocommutative coassociative graded connected coalgebra. We generalize the coproduct to the algebraic…
On the decomposition of connected graphs into their biconnected components
Angela Mestre
We give a recursion formula to generate all equivalence classes of biconnected graphs with coefficients given by the inverses of the orders of their groups of automorphisms. We giv…