
EXAMPLE

We represent ordered trees by their corresponding Dyck paths via the "glove" bijection.
The "tree" UDUUDD has 2 drawings:
* , UD, UUDD, UDUUDD and *, UD, UDUD, UDUUDD;
the "tree" UUDDUD has 2 drawings:
*, UD, UUDD, UUDDUD and *, UD, UUDD, UUDDUD.
Thus A(3,2)=2.
The "tree" UUUDDD has 1 drawing: *, UD, UUDD, UUUDDD;
the "tree" UUDUDD has 1 drawing: *, UD, UUDD, UUDUDD;
the "tree" UDUDUD has 1 drawing: *, UD, UDUD, UDUDUD.
Thus A(3,1)=3.
Triangle starts:
1;
2;
3, 2;
4, 2, 6, 1, 1;
5, 2, 6, 9, 1, 4, 4, 4, 2, 1, 2, 2;
