how to solve recurances?



On Sunday 19 January 2003 09:15 pm, wang yin wrote:
> No. I don't mean I want to get a value of T(3) or T(1000), ...
>
> I want the result: T(n)=2^n-1;
>
> That's the answer to the recurence
>
> T(n)=2*T(n-1)+1, T(0)=0
>

check out differ.mac: 
demo("differ.dem");
(C8) f[0]:0;
(D8)                                   0
(C9) f[n+1]=2*f[n]+1;

(D9)                           f      = 2 f  + 1
                                n + 1      n
(C10) difference(%,f[n]);

                                            n
(D10)                             f  = 2  - 1
                                      n

differ.mac  in the share/algebra solves 1st and second order recurrence 
equations.

Osman