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Say I want to run a function of the form

Table[i*j,{i,-5,5},{j,-5,5}]

but I want to omit all the values of $|i|\leq1$ and $|j|\leq1$. In other words, how do I create my 2D grid of values that doesn't contain the box of length 2 centered at the origin.

How would I write this in a general form rather than making the table by hand?

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  • $\begingroup$ You mean you want to skip $i=-1,0,1$ and $j=-1,0,1$? $\endgroup$
    – Nasser
    Apr 27, 2020 at 16:37
  • $\begingroup$ Yes, exactly. I want to skip the 9 pairs ${i,j}$ where $i=-1,0,1$, $j=-1,0,1$ $\endgroup$
    – flyingdutchman
    Apr 27, 2020 at 16:40

3 Answers 3

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And just for fun, here is another approach

Flatten[Table[If[Abs[i]<= 1 || Abs[j] <=1, Nothing[], i*j], {i, -5, 5}, {j, -5, 5}], {2}]

Mathematica graphics

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  • $\begingroup$ My question was probably not sufficiently clear. This is what I was looking for but exchanging the Or ( || ) for an And ( && ). Thanks! $\endgroup$
    – flyingdutchman
    Apr 27, 2020 at 17:20
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One approach is to explicitly set the range for the variables:

ran = Select[Range[-5, 5], Abs[#] > 1 &];
Table[i*j, {i, ran}, {j, ran}]
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Another one to try to get me to 10K.

With[{r = Join[#, -Reverse@#] &@Range[-5, -2]}, Table[i j, {i, r}, {j, r}]]
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