Re: Simple Recursive Map

*To*: mathgroup at smc.vnet.net*Subject*: [mg35428] Re: [mg35398] Simple Recursive Map*From*: Hugh Walker <hwalker at gvtc.com>*Date*: Fri, 12 Jul 2002 04:28:43 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

On Thursday, July 11, 2002, at 04:24 AM, Reuben wrote: > I have the map > > x_n+1=y_n-a*(x_n)^2 - 1 > y_n+1=b*x_n > > If I specify a,b, x_0 and y_0, how can I make Mathematica iterate > through this numerically to give me x_50 and y_50? > > Thanks > Reuben I think this is what you want. x[n_] := y[n - 1] - a*x[n - 1]^2 - 1 y[n_] := b*x[n - 1] {a, b, x[0], y[0]} = {1, 1, 1, 1}; The first few results are Table[{x[k], y[k]}, {k, 7}] {{-1, 1}, {-1, -1}, {-3, -1}, {-11, -3}, {-125, -11}, {-15637, -125}, {-244515895, -15637}} ============ Hugh Walker Gnarly Oaks