  The Ramanujan polynomials were introduced by Ramanujan in his study of power
series inversions. In an approach to the Cayley formula on the number of trees,
Shor discovers a refined recurrence relation in terms of the number of improper
edges, without realizing the connection to the Ramanujan polynomials. On the
other hand, Dumont and Ramamonjisoa independently take the grammatical approach
to a sequence associated with the Ramanujan polynomials and have reached the
same conclusion as Shor's. It was a coincidence for Zeng to realize that the
Shor polynomials turn out to be the Ramanujan polynomials through an explicit
substitution of parameters. Shor also discovers a recursion of Ramanujan
polynomials which is equivalent to the Berndt-Evans-Wilson recursion under the
substitution of Zeng, and asks for a combinatorial interpretation. The
objective of this paper is to present a bijection for the Shor recursion, or
and Berndt-Evans-Wilson recursion, answering the question of Shor. Such a
bijection also leads to a combinatorial interpretation of the recurrence
relation originally given by Ramanujan.
