Cattleya numbers can be used in two scenarios (programming)
- n elements are pushed onto the stack, and there are several ways to pop them out of the stack.
- How many different forms of binary trees can be composed of n different elements?
The first few terms of Cattleya's number are
1,1,2,5,14,42,132,429,1430,4862,16796,58786,208012,742900,2674440,9694845,35357670,129644790,477638700,1767263190,6564120420,24466267020,91482563640,343059613650,1289904147324,4861946401452 …The formula for Cattleya number is
For example:
5 elements are pushed onto the stack
So there are total
method of popping the stack
Another example (dry cough)
There are 4 different elements forming different forms of binary trees, which can be formed in total
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