Re: Recursive function

*To*: mathgroup at smc.vnet.net*Subject*: [mg115930] Re: Recursive function*From*: Dana DeLouis <dana2010 at me.com>*Date*: Wed, 26 Jan 2011 05:05:33 -0500 (EST)

> On Jan 25, 4:20 am, StatsMath <stats.ma... at gmail.com> wrote: > I am trying to compute the following function: > > x[t] = a * x[t-1] + b * x[t-2] > x[0] = 1 > x[1] = 1 Probably not useful, but another way for a specific term in your sequence might be: (Similar to the Fibonacci sequence) term[n_, a_, b_] := Tr[MatrixPower[{{a, 1}, {b, 0}}, n][[All, -1]]] Given a=1, b=1/2, then the 20th term: term[20, 1, 1/2] 413403 / 1024 = = = = = = = = = = HTH : >) Dana DeLouis