Context-Free Grammars for Several Triangular Arrays
Roberta Rui Zhou, Jean Yeh, Fuquan Ren · Axioms · 2022
In this paper, we present a unified grammatical interpretation of the numbers that satisfy a kind of four-term recurrence relation, including the Bell triangle, the coefficients of modified Hermite polynomials, and the Bessel polynomials. Additionally, as an application, a criterion for real zeros of row-generating polynomials is also presented.