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Re: iterative function query

• To: mathgroup@smc.vnet.net
• Subject: [mg10620] Re: iterative function query
• From: Allan Hayes <hay@haystack.demon.co.uk>
• Date: Tue, 27 Jan 1998 03:09:48 -0500
• References: <6a1r14$q71@smc.vnet.net>

Eric Walters wrote:
> 
> Can someone explain the best way to code:
> 
> starting at x=1 and going to x=5;
> taxes[x_]:= 45 + 0.97(taxes[x+1])/; 
> 
> so that the following is generated:
> 
> 45 + 0.97(45+0.97(45+0.97(45+0.97(45))))

Eric:

Nest[(b +a(#))&,0, 5]

b + a (b + a (b + a (b + a b)))

%/.{a->.97, b->45}

211.899

or, in one line

Nest[(45 +.97(#))&,0, 5]

211.899

-- 
Allan Hayes
Training and Consulting
Leicester, UK
hay@haystack.demon.co.uk
http://www.haystack.demon.co.uk
voice: +44 (0)116 271 4198
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