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Re: building a list containing elements f(i,j)

• To: mathgroup at smc.vnet.net
• Subject: [mg71079] Re: [mg71045] building a list containing elements f(i,j)
• From: János <janos.lobb at yale.edu>
• Date: Wed, 8 Nov 2006 06:04:31 -0500 (EST)
• References: <200611060752.CAA08745@smc.vnet.net>

On Nov 6, 2006, at 2:52 AM, xarnaudx at gmail.com wrote:

>
> hi,
> i want to construct a list of the form:
> { f[1,1], ... f[n,m] }
> So the list contains elements of the form f[i,j] with i ranging from 0
> to n, and j from 0 to somebound[i].
>
> What would be the most elegant way to this?
> thanks

Here is newbie elegancy:

In[1]:=
n = 4;

In[2]:=
Flatten[Table[Table[f[i, j],
     {j, 0, i}], {i, 0, n}]]
Out[2]=
{f[0, 0], f[1, 0], f[1, 1],
   f[2, 0], f[2, 1], f[2, 2],
   f[3, 0], f[3, 1], f[3, 2],
   f[3, 3], f[4, 0], f[4, 1],
   f[4, 2], f[4, 3], f[4, 4]}

János


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• References:
  • building a list containing elements f(i,j)
    • From: "xarnaudx@gmail.com" <xarnaudx@gmail.com>