Sorry if this is a bit confusing. I'm told this is basic but I have no idea how to show that a5 = 14. Thank you
We define four sequences an,bn, cn, dn in quite different ways. You have to show that they in fact are the same sequence. You also have to compute generating function of this sequence and get the explicit formula for an. A sequence an. Let n 2 1. denote by an the number of all possible different Zn having the order of variables unchanged. For bracketings in the product xi n = 3 we have the following bracketing (12)3, TI(23) Hence a3 = 2. For n = 4 we have 5 bracketing
Hence a4-5. It will be convenient to put Show that a 14.
